Brubaker (1-0) allowed one run and four hits in 5 1/3 innings with four strikeouts and one walk. His two-run single down the right-field line capped a three-run second inning and gave the Pirates a 3-1 lead.
“I just wanted to put the ball in play,” said Brubaker, who is 2 for 4 this season after also getting a hit in his first career at-bat. “He threw me a fastball and I put a swing on it. If you asked me where it was in the zone, though, I couldn’t even tell you. I’m not that kind of hitter.”
Pittsburgh’s Bryan Reynolds had the third four-hit game of his career.
Trevor Williams (1-1) was hit hard in his return to Pittsburgh, where he spent the first five seasons of his career before being released in November. He was tagged for five runs and 10 hits in 3 1/3 innings.
Pirates catcher Jacob Stalllings said it felt strange to face Williams, who received a video tribute on the scoreboard when he warmed up in the first inning.
“Trevor is one of my really good friends and I just didn’t want to face him,” Stallings said. “It was weird, for sure.”
Wilmer Difo hit his first career pinch-hit home run as Pittsburgh won consecutive games for the first time this season.
Javier Báez accounted for the Cubs’ run with a second-inning homer. Chicago lost for the fourth time in five games and went 1 for 23 with runners in scoring position in losing two of three to Pittsburgh.
The Cubs have had five hits or fewer in six of their first nine games.
“I’m confident in this lineup,” Williams said. “We have guys who can take the ball out of the ballpark on any pitch. When we find our groove, it’s going to be fun to watch.”
Dustin Fowler pulled the Pirates into a 1-1 tie in the second with a run-scoring double immediately before Brubaker delivered his single. Brubaker drove into another run with a grounder in the fourth, and Colin Moran had an RBI single in the fifth.
Difo’s two-run blast in the seventh made it 7-1.
“We had guys really execute pitches, those guys late and Brubaker really executed the (game) plan well,” Stallings said.
Pirates: 3B Ke’Bryan Hayes (left wrist strain) is not yet able to swing a bat, and GM Ben Cherington said there is no timetable for the rookie’s return. “We’re not going to rush this,” Cherington said. … RHP Cody Ponce (right forearm tightness) is scheduled to pitch a three-inning simulated game this week.
YOU’VE BEEN WARNED
Home plate umpire and crew chief Greg Gibson warned both managers after Brubaker hit Kris Bryant on the left arm with a pitch in the fourth. An inning earlier, Contreras was clipped on the upper left arm.
Contreras was clearly agitated and admitted after the game he is frustrated after being hit three times already this year.
Cubs catching coach Mike Borzello was ejected for arguing the warning from the dugout.
There were no batters hit after the warning.
RUN TAKEN AWAY
The Cubs appeared to score a run in the third on a throwing error by shortstop Kevin Newman, but the umpire’s call was reversed to an inning-ending double play following a replay review
Baserunner Willson Contreras was ruled to have interfered with Newman, who was trying to complete the relay throw to first to complete a double play on a grounder hit by Anthony Rizzo. Ian Happ had advanced from second to home on the wild throw.
Cubs manager David Ross said he did not receive an explanation from Gibson.
Fantasy baseball closer stock watch: Remember Michael Fulmer?
Eric Karabell takes his weekly look at the never-ending carousel of fantasy baseball closers, including a former Rookie of the Year returning to the fantasy mix in Detroit.
New York Mets OF Kevin Pillar has multiple nasal fractures after being hit in face by pitch
Mets outfielder Kevin Pillar has multiple nasal fractures after being hit in the face by a 94 mph fastball in Monday night's win over the Braves.
Fantasy baseball forecaster: Pitcher projections for the next 10 days
Keep up to date on who is pitching -- and how well they're expected to do -- with our forecaster, which provides a rolling 10-day outlook of every team's probable starting pitchers with game score projections.
Fantasy baseball forecaster: Team hitting ratings
Stay ahead of the game and optimize your fantasy baseball hitters with our forecaster, which provides a rolling 10-day outlook of every team's hitting matchups as well as the potential for stolen bases.
MLB's new dead ball era: How much is changing the baseball actually changing baseball?
We crunch the numbers to find out if the new ball is helping or hurting -- or even making any difference at all.
Marlins to take on Phillies on the road
Miami Marlins (18-22, fourth in the NL East) vs. Philadelphia Phillies (21-20, second in the NL East)