Real or not? Six big-picture themes that will shape the 2018 season

The offseason dragged on forever with all the late signings. Spring training always drags on too long. Where I live, we've been hammered by a series of Nor'easters. It's safe to say Opening Day has never felt like it has arrived at a better time. With the season about to kick off, here is a rundown of some of the big-picture issues to watch:

The ball

From 2014 to 2015, home runs across the majors increased 17.3 percent. From 2015 to 2016, home runs jumped another 14.3 percent. In 2017, they increased 8.8 percent, resulting in a record 6,105 home runs -- a 46 percent increase over three seasons and an average of 64 more home runs per team than in 2014. Independent investigations have shown that the ball, while remaining within MLB regulations, has changed (not necessarily intentionally), helping to fuel this power surge. As a result, Major League Baseball will standardize how all 30 clubs store baseballs in 2018. As first reported by Sports Illustrated's Tom Verducci in February, baseballs must be stored in an "air-conditioned and enclosed room."

On top of that, the Diamondbacks, who play in one of the most hitter-friendly parks in the majors, will hold their baseballs in a humidor maintained at 70 degrees and 50 percent humidity. That should level out offense at Chase Field. One estimate has Chase Field's park factor being reduced from 116 (run scoring is increased 16 percent) to 100 (a neutral park). When the Rockies shifted to a humidor in 2002, there were 96 fewer runs scored at Coors Field than in 2001, a 9 percent decrease.

Do the new guidelines mean we'll see fewer home runs in 2018? We almost certainly will at Chase Field, but it's unclear how standardized conditions across all 30 teams will affect home runs, given previously dissimilar storage conditions. It's possible it will merely stem yet another increase. Maybe it will cause a sharp decline. Maybe it will have no impact whatsoever. For what it's worth, home runs have been up slightly in spring training compared to spring training in 2017.

If home runs are harder to come by, which team is most affected? The Rays scored the highest percentage of their runs via the home run in 2017, but they have a much different roster without Logan Morrison, Steven Souza Jr. and Evan Longoria, who combined for 88 home runs. The Orioles have long relied on the home run. They were eighth in the AL in runs in 2017, even though they ranked 13th in on-base percentage, a one-dimensional type of attack that might struggle with fewer home runs. The Astros, on the other hand, were second in the majors with 238 home runs and first in runs but had a well-balanced offense, ranking first in batting average and fewest strikeouts, so they should field an offensive powerhouse regardless of the ball.

Six-man rotations are coming

The Angels announced that they will use a six-man rotation -- in part to protect Shohei Ohtani, who pitched once a week in Japan, and in part to help protect an entire rotation of starters who have battled injuries in recent seasons. New Mets manager Mickey Calloway has suggested that his team will probably use a six-man rotation at times. The Rangers expressed the possibility of using a six-man rotation before Cole Hamels voiced his displeasure with that idea. "It's not part of baseball. I know that's the new analytical side of trying to reinvent the wheel, but I was brought up in the minor leagues on the five-man, and that's what I'm designed and conditioned for," he told reporters after a game in early March.

Maybe somebody should show Hamels the numbers. Last year, he had a 4.72 ERA in 16 starts with four days of rest and a 3.20 ERA in eight starts with five or more rest days. On regular rest, he allowed 16 home runs in 97.1 innings; on longer rest, he allowed two in 50.2 innings.

Of course, that's a small sample and might not tell us about Hamels in 2018. Then again, in 2016, he had a 3.65 ERA in 18 starts with four days of rest and a 3.28 ERA in 14 starts with long rest. But across MLB in 2017, starters posted a 4.50 ERA on four days of rest, 4.44 on five and 4.50 on six or more.

Teams have actually been going to more rest for their starters for years -- and there will be four additional scattered off days this season to provide even more rest. The Dodgers manipulated their rotation to such an extent in 2017 that they made 115 starts on five or more days of rest. The Yankees made 109 such starts. Both teams made the playoffs. The MLB average was 85 starts on long rest -- a little more than half of all starts. A decade ago, the average was 74 long starts per team, and in 1997, the average was 64.

As another point of comparison, Clayton Kershaw has made 54 percent of his career starts on four days of rest. Greg Maddux made 66 percent of his starts on four days of rest (and another 5 percent on three days). The idea that even your best starter pitches every fifth day has been slowly withering away for two-plus decades.

(On the other end of the spectrum, the Rays have announced a plan to use a four-man rotation for 2018, with a bullpen game scheduled for whenever the team needs a fifth starter. Manager Kevin Cash's idea is to concentrate as many starts as possible with his top four guys, keeping them pitching every fifth day.)

The bullpen revolution will continue

Even though starters are pitching less frequently, that doesn't mean they're chewing up more innings when they pitch. Look at the percentage of innings thrown by starters since 2010:

2010: 67.1

2011: 67.3

2012: 66.0

2013: 65.7

2014: 66.5

2015: 65.0

2016: 63.3

2017: 61.9

This is the inevitable result of three factors: (1) The numbers that suggest starters in general fare worse the third time through the lineup; (2) More relievers throwing harder than ever; (3) The increased size of bullpens, allowing those relief innings to be distributed among seven or eight relievers.

Indeed, it's possible that the future of pitching is not the six-man rotation but Tampa Bay's hybrid four-man/bullpen rotation. If starters are pitching only six innings per game or maxing out at 100 pitches anyway, why not start your best pitchers every fifth day?

Either way, bullpen depth is more important than ever. Bullpens are also volatile and difficult to project. FanGraphs projects the Yankees -- by a wide margin -- to have the best bullpen in the majors. Nobody is going to disagree with that. The Astros are a solid No. 2, with the Indians, Cubs and Brewers rounding out the top five. Among the top playoff contenders, the Diamondbacks project as the shakiest pen, ranking 26th in value (although Cardinals fans seem worried about their bullpen).

The superteams

The Dodgers, Indians and Astros each won 100 games last season, marking the first time there were three 100-win teams since the Braves, Yankees and Giants in 2003. The Nationals won 97 games last season, the Red Sox won 93 games (and eventually signed J.D. Martinez), the Cubs won 92 games despite going 43-45 in the first half, and the Yankees won 91 games and then acquired NL MVP Giancarlo Stanton to boost their 2018 outlook.

Last season, all six preseason favorites won their divisions, with four races decided in blowouts and only the AL East race undecided going into the final weekend. One reason the free-agent market unfolded the way it did this winter was the strength of these seven teams. The risk of signing free agents who offered mostly minimal upgrades wasn't worth the money for most front offices.

Will we have the same anticlimactic division races in 2018? Once again, the AL East race between the Yankees and Red Sox appears close -- though the Yankees will begin as the consensus pick -- while the other five divisions feature heavy favorites. It would seem unlikely, however, that all six favorites will once again capture their divisions. That rarely happens, let alone two seasons in a row.

We can only hope that history wins again and we'll get an upset somewhere. Good luck picking which division that will be. Maybe it's the Twins in the AL Central or the Brewers in the NL Central or the Diamondbacks over a Dodgers team that suffers a post-World Series letdown.

The youth is still rising

The demographics of baseball continue to change, as research shows that players are peaking earlier and declining faster than they did in the steroid era. The weighted age for players has continued to drop since the early 2000s as younger players compile more positive value. Last year gave us Aaron Judge, Cody Bellinger, Andrew Benintendi, Ian Happ, Josh Bell, Jordan Montgomery, Luis Castillo, Manuel Margot and Paul DeJong, among others. Some of the partial season standouts included Rhys Hoskins, Matt Olson, Matt Chapman, Josh Hader, Yoan Moncada, Rafael Devers and Ozzie Albies. Judge was the old man of the group, the only player in his age-25 season.

This season promises more of the same. Ohtani will attempt to play both ways with the Angels. Although Ohtani has struggled in spring training, Braves phenom Ronald Acuna -- regarded as the game's top prospect -- has been one of the best players in Florida. While Acuna will begin the season in the minors thanks to service-time manipulation, the outfielder will be up quickly -- maybe even after a couple of weeks -- and looks ready to make an impact at 20 years old. Other top rookies could include Scott Kingery and J.P. Crawford of the Phillies, Nick Senzel and Tyler Mahle of the Reds, Lewis Brinson of the Marlins, Michael Kopech of the White Sox, Walker Buehler of the Dodgers, Kyle Tucker of the Astros and Luiz Gohara of the Braves. Some of those guys will start in the minors, but all should reach the majors at some point.

Two of the most intriguing potential rookies are sons of major leaguers, Fernando Tatis Jr. and Vladimir Guerrero Jr. Both are still teenagers, but it's not out of the question that they could arrive in the majors at 19, as Bryce Harper and Mike Trout did. Both played in the Midwest League last season but are advanced enough with the bat that they could start in Double-A and push for the big leagues come August or September.

Pace of play

Ah, everyone's favorite topic. There will be no pitch clock in 2018 -- at least at the major league level -- but commissioner Rob Manfred did institute some new rules to speed up the average game time. The most significant change is limiting mound visits to six per team per nine innings (not including pitching changes). Catchers such as Martin Maldonado and Willson Contreras have already said they won't follow the rule and are willing to accept any fines levied against them, though it remains to be seen what the fines and/or punishment will be, given that specifics weren't spelled out.

Aside from that, there were parameters set in place to speed up the action between innings, during pitching changes and with replay reviews. The pace-of-play initiative to watch, however, is at the minor league level, where Double-A and Triple-A games will use a 15-second pitch clock with no runners on base (and a clock at 20 seconds with runners on base). Call that a trial run for the big leagues. A more controversial change in the minors -- though far less likely to be instituted at the major league level (at least in 2019) -- was the announcement that extra-inning games will begin with a runner on second base.

Whether you love that idea or hate it, baseball will survive. It always does.