Saracens will be aiming to stretch their advantage at the top of the Aviva Premiership table when they travel to the Twickenham Stoop to take on Harlequins in Saturday's game of the day.
Quins will be aiming to become the first side to defeat the early pace-setters this season, with three successive bonus-point victories placing the north London club top of the standings.
However, no side in Premiership history has launched a league campaign by claiming four successive maximum-point victories.
Wing Tom Williams will make his 200th Harlequins appearance, while Nick Easter continues in the second row alongside George Robson. Danny Care and Nick Evans again make up the half-back pairing while Matt Hopper comes onto the bench in place of Sam Smith.
Saracens boss Mark McCall makes just the solitary change from the handsome victory over Bath last time out, as Scotland international Kelly Brown comes into the back row, at the expense of Ernst Joubert, after recovering from an ankle injury.
In the day's other games, Bath will be hoping to bounce back from the 31-17 defeat at Sarries when they tackle London Irish at the Recreation Ground.
Lock Dave Attwood returns to captain Bath, while Wales prop Paul James adds a potency to their front row. Peter Stringer and George Ford blend experience and youth at half-back, while Matt Banahan starts on the wing and Kyle Eastmond forms an exciting centre pairing with Jonathan Joseph.
Irish make three personnel changes for the trip. Leo Halavatau comes in for the injured Halani Aulika at tighthead prop while Kieran Low and Alex Lewington are named at openside flanker and on the wing respectively, with Topsy Ojo moving to full-back.
Only two teams have yet to win after three outings this season and they meet at Adams Park on Saturday when Wasps clash with Worcester.
Elliot Daly returns for injury-hit Wasps to take over the full-back slot, with backs Tom Varndell, Hugo Southwell and Andrea Masi all sidelined.
Nathan Hughes makes his first start for the club at number eight, having impressed off the bench last week.
Worcester loosehead prop George Porter will make his first Warriors appearance for nine months as he returns from shoulder surgery. Prop Euan Murray and lock Chris Jones return to the side while Semisi Taulava comes in at number eight.