Owen Farrell will be England's sole captain against Ireland, with Dylan Hartley unavailable for the start of the Six Nations due to injury.
Billy Vunipola marked his Saracens return with a try but it was not enough to stop the defending Premiership champion slipping to a 24-18 defeat against Sale Sharks.
Saracens closed the gap on Premiership leader Exeter Chiefs by producing a second-half fightback to beat Worcester Warriors.
Exeter Chiefs ended Saracens' 22-match unbeaten run win a 31-13 bonus-point victory to replace the champion at the top of the Premiership and Leicester Tigers halted its eight-match losing streak.
Billy Vunipola capped an outstanding display by scoring the decisive try in Saracens' 25-20 derby win over Harlequins in the Premiership.
Last season's Premiership finalist Saracens and Exeter Chiefs maintained their unbeaten starts to the new campaign with wins in the Premiership.
Sergio Aguero struck twice, while Vincent Kompany, Fernandinho and Gabriel Jesus were also on target as Manchester City thumped Watford 5-0.