Charles Piutau, Chris Ashton and other new Premiership signings to watch this season

(From L to R) Alex Curthbert, Jaco Kriel, Charles Piutau, Dan Biggar and Nathan Earle are all new signings to watch in the Premiership this season. ESPN/Getty

The 2018-19 Premiership season finally gets underway this weekend, with the clash between newly-promoted Bristol Bears and Bath opening the campaign on Friday night. After winning their third Premiership title in four years last season, Saracens will be the team to beat once again while Exeter Chiefs, Wasps and Leicester Tigers are tipped to provide the challenge.

Ahead of the new season, here are the top 10 new signings to keep an eye on this campaign.

Charles Piutau - Bristol Bears

Bristol shocked the rugby world when they announced the signing of Piutau on a reported £1 million-per-season deal. It makes the New Zealand fullback the most expensive rugby player on the planet and the 26-year-old's return to the Premiership following a two-year spell at Ulster has grabbed the attention of players and fans alike.

The former Wasp made 17 appearances for the All Blacks before making his move to Europe in 2015 but has since only strengthened his reputation as one of the world's most exciting players. His arrival at Bristol also reunites him with elder bother Siale and fellow Kiwi Pat Lam, who coached Piutau at the Blues back in New Zealand. Bristol's millionaire owner Steve Lawnsdown will have a nervous wait to see if his star signing will ready for the start of the campaign however, after Piutau picked up a shoulder injury in the last week of pre-season.

Alex Cuthbert - Exeter Chiefs

Exeter made Cuthbert their only senior signing over the summer but pulled off a real coup by securing the services of the Wales and British and Irish Lions winger. Cuthbert, 28, is at the stage of his life where he is ready to try something new and has effectively decided to end his international career in order to leave Cardiff Blues and sign with the Chiefs.

Cuthbert arrives looking to rediscover the form that made him such a decisive player for his country. He scored crucial tries for Wales in their Six Nations title-winning campaigns of 2012 and 2013, as well as scoring for the Lions against Australia that summer. He joins a young, exciting Chiefs setup that will be out for revenge after having lost its Premiership crown to Saracens in May's Premiership final.

Brad Shields - Wasps

Capped by England before even making his Premiership debut, it's fair to say a lot of people will be watching Shields' performances for Wasps with interest this campaign.

Let's go back a step. Born in New Zealand to English parents, Wasps announced the signing of the Hurricanes captain in November 2017. A few months later, Shields, who had been capped by the All Blacks at under-20 level but never by the senior side, declared himself available for England selection.

A call-up from Eddie Jones duly followed and the flanker made his Test debut in England's tour of South Africa in June, weeks before even arriving at the Ricoh Arena. Known for his physicality, work-rate and flexibility across the back-row, it will be interesting to see how the 27-year-old stands up to the challenges of the Premiership and whether he can keep his place in Jones' squad.

Dan Biggar - Northampton Saints

After a record-breaking 11 seasons at Ospreys, Biggar arrives at Northampton in search of a new challenge. In his final appearance for the Pro 14 side, the Wales fly-half broke Dan Parks' record to become the league's all-time leading points scorer -- an impressive achievement at the age of just 28.

There has been a lot of change at Franklin's Gardens since the British and Irish Lion agreed to join in September 2017. After finishing a disappointing 9th last season, Director of Rugby Jim Mallander was replaced by the experienced New Zealand coach Chris Boyd. The former Hurricanes boss has a reputation for attacking rugby and Biggar could thrive under his guidance.

Jaco Kriel - Gloucester

Along with Franco Mostert, Ruan Dreyer and Franco Morais, Kriel is one of four South African players to link up with former Lions coach Johan Ackermann at Kingsholm Stadium. Ackermann made Kriel his captain during their time together at the Super Rugby side, and has now handed the 29-year-old a chance for a fresh start following an injury-hit 12 months.

Kriel has won 11 caps for the Springboks since making his debut against Ireland in 2016 and has earned a reputation as one of the hardest-working flankers in the game. He hasn't featured since September 2017, however, due to a shoulder injury, and underwent further surgery in March. Gloucester will be hoping Kriel will quickly get up to speed as he joins a back row that also includes Ackermann's 23-year-old son, Ruan.  

Chris Ashton - Sale Sharks

Ashton's return to the Premiership was never going to be a quiet one. After an impressive year in Toulon -- in which Ashton scored 24 tries to break the Top 14's single-season record - the 31-year-old moved back to England due to family reasons, signed with Sale and subsequently received a recall to the England squad.

Or so it seemed. There's never a dull moment where Ashton is concerned and the winger will now miss the first six rounds of the campaign after being sent off in a pre-season friendly for a dangerous tackle. Ashton will be looking for redemption when he returns in November, not to mention the all-time Premiership try-scoring record. The winger is currently 12 tries short of Tom Varndell's record of 92.

George Smith - Bristol Bears

At the age of 38, Australian rugby legend Smith is showing no signs of slowing down. Although he has only signed with newly-promoted Bristol on a six-month injury-cover deal, the flanker is expected to make a big impact on his return to the Premiership. Smith has fond memories of the league and was Wasps' Player of the Year in his sole season there in 2015-16.

Capped 111 times by Australia, easier options were available to Smith after leaving Suntory Sungoliath in Japan, but the forward is genuinely determined to challenge himself and improve as a player -- even at this stage of his career. Smith is held in such esteem that Eddie Jones describes the flanker as the greatest player he's ever seen.

Francois Venter - Worcester Warriors

Venter arrives at Sixways Stadium on the back of an outstanding season for South Africa's Cheetahs in the Pro 14. The centre was named in Opta's Team of the Season after making the most clean breaks in the league, as well as ranking well in metres gained and offloads.

The 27-year-old, who has been capped by the Springboks seven times, captained the Cheetahs in their debut season in Europe as the team made the playoffs. Venter joins head coach Rory Duncan in swapping the Cheetahs for the Warriors and the pair will link up with fellow South African Alan Solomons, who was named Director of Rugby last year.

Paul Lasike - Harlequins

Lasike's debut Premiership campaign will be watched with interest on both sides of the pond. Born in Auckland, New Zealand in 1990, Lasike made his name in rugby playing for Brigham Young University in the U.S., winning four national championships. Lasike's physical abilities attracted the attentions of a different sport -- the NFL.

Lasike converted to an NFL fullback but after spending two seasons on the fringes of the Chicago Bears' roster, the 28-year-old switched back to rugby, signing with the Utah Warriors in 2017. Now playing as a powerful centre, Lasike has gone on to make six appearances for the U.S. national team, impressing in the Eagles' 30-29 win against Scotland in June.

Nathan Earle - Harlequins

Earle departed Saracens in style as he came off the bench to score the final try of May's Premiership final victory over Exeter. The 23-year-old had already agreed to join Harlequins five months earlier, and arrives at the Stoop looking for more game time in order to impress England coach Eddie Jones.

The Hong Kong-born winger is yet to receive his first full England cap but was in Jones' squad for the 2018 Six Nations and the summer tour of South Africa. A player with glittering talent and potential, Earle's progress was halted by a torn Achilles in 2014 that ruled him out for a whole year. After making a career-high 14 Premiership appearances last campaign, but only seven starts, Earle will be hoping more regular action will aid his push for a first England cap and a World Cup spot.