The weekend's headline fixture in the Aviva Premiership is Saracens hosting Northampton at Allianz Park on Sunday in what is likely to be a dress rehearsal for the Premiership final at Twickenham on May 31.
Sarries boss Mark McCall has made three changes to the team that beat 14-man Ulster in the Heineken Cup last weekend, with Alex Goode replaced at full-back by Chris Wyles.
Argentine centre Marcelo Bosch comes in for Duncan Taylor and Saracens double-centurion Neil de Kock replaces Richard Wigglesworth at half-back.
"It's a big game, first against second. We understand that against them there will be only one important match, which will be the semi-final or the final," McCall said.
Saints have made fully 12 changes to their starting line-up from the team that beat Sale in their Amlin Challenge Cup tie last weekend.
Stephen Myler is a big name coming back into fold at fly-half, along with number eight Samu Manoa, who is back after helping the USA to qualify for the Rugby World Cup next year.
The only three men who keep their place from the game at Sale are Ben Foden, Ross McMillan and Lee Dickson as Saints look at a different line-up.
In Sunday's other fixture, Newcastle Falcons have four players back from injury for the trip to fellow strugglers London Irish.
Falcons skipper Will Welch, centre Jamie Helleur, winger Ryan Shortland and hooker Matt Thompson all return and there are three further changes to the XV beaten at home by bottom side Worcester a fortnight ago.
Rugby League convert Lee Smith is in for Danny Barnes at centre, while fly-half Rory Clegg gets the nod with Noah Cato switching to full-back due to Shortland's inclusion on the wing.
Thompson and loosehead Grant Shiells form a new look front row alongside tighthead Oliver Tomaszczyk, who retains his place.
Academy product Gerard Ellis is one of six changes to the London Irish starting XV, including a return for skipper George Skivington.