Wasps and Harlequins will face off against each other for the fourth time already this season at the Ricoh Arena on Sunday.
While Quins lead the head-to-head two wins to one, it was Wasps' big away win in January that set them on course for a European Champions Cup quarter-final spot, at the expense of Conor O'Shea's side.
In the Premiership, Quins got the better of Wasps at the Stoop earlier in the season, and come into the game in good form as they try to close the gap on the top four.
Northampton and Bath seemed to have opened up a sizable gap at the top of the table, with Saracens well-placed in third. However the battle for the fourth and final play-off spot is incredibly tight, with Wasps currently headed to the semi-finals.
They are just two points clear of Quins, in seventh, with eighth-placed Sale also within two points of the top four.
With such little margin for error, both sides know it's a must-win game.
Wasps are boosted by the return of Welsh lock Bradley Davies, who is named in the starting line-up, having been released back to the Club by Wales before their RBS 6 Nations match against Scotland.
There are also returns for England Saxons Joe Simpson, Christian Wade, Matt Mullan and James Gaskell after a week off during the LV=Cup, who join fellow Saxons Elliot Daly and Jake Cooper-Woolley in the side.
James Downey, who arrived this week on loan from Glasgow Warriors for the remainder of the season, is set to make his Wasps debut in the centre, alongside Elliot Daly. Downey arrives as injury cover for Chris Bell and Alapati Leiua.
Thomas Young, Ed Jackson and Will Helu retain their places in the side after impressing in the LV=Cup, with Helu moving from the centre to the wing.
Meanwhile for Quins Ugo Monye is named at full-back, in a completely changed backline, with Marland Yarde and Charlie Walker returning to the starting XV on the wings. Matt Hopper and George Lowe resume their centre partnership, while Nick Evans and Danny Care are named at fly-half and scrum-half respectively.
In the pack Kyle Sinckler returns at prop, with Charlie Matthews and George Robson starting in the second row. Jack Clifford is named at number eight. Among the replacements Dave Ward returns after recovering from injury.
Form: Wasps' 26-39 defeat at Bath in round 13 of Aviva Premiership Rugby ended a three game winning run in the tournament – they have tallied three try bonus points in their last four games and scored three tries in the other. Wasps have not been defeated in a home fixture in Aviva Premiership Rugby since Saracens visited Adams Park on 29th March. Harlequins have tallied two maximum point victories, against London Welsh and Leicester in the last two rounds of Aviva Premiership Rugby, and have not achieved three successive "five-pointers" in the tournament since the start of the 2012/13 season. The two sides have already met on three occasions this season with each side winning its respective away game in the European Champions Cup, and 'Quins victory at Twickenham Stoop in round 3 of Aviva Premiership Rugby. Wasps only victory over Harlequins in the tournament in their last nine encounters since 2009 was 17-16 at the Stoop on 9th February 2013.
Wasps: 15 Rob Miller, 14 Christian Wade, 13 Elliot Daly, 12 James Downey, 11 Will Helu, 10 Andy Goode, 9 Joe Simpson, 8 Nathan Hughes, 7 Thomas Young, 6 Ed Jackson, 5 Kearnan Myall, 4 Bradley Davies, 3 Jake Cooper-Woolley, 2 Edd Shervington, 1 Matt Mullan (c)
Replacements: 16 Carlo Festuccia, 17 Simon McIntyre, 18 Lorenzo Cittadini, 19 James Gaskell, 20 Guy Thompson, 21 Tom Bliss, 22 Alex Lozowski, 23 Tom Varndell
Harlequins: 15 Ugo Monye, 14 Marland Yarde, 13 Matt Hopper, 12 George Lowe, 11 Charlie Walker, 10 Nick Evans, 9 Danny Care, 8 Jack Clifford, 7 Luke Wallace, 6 Joe Trayfoot, 5 George Robson (c), 4 Charlie Matthews, 3 Kyle Sinckler, 2 Joe Gray, 1 Mark Lambert
Replacements: 16 Dave Ward, 17 Darryl Marfo, 18 Seb Adeniran-Olule, 19 Sam Twomey, 20 Netani Talei, 21 Karl Dickson, 22 Ben Botica, 23 Ollie Lindsay-Hague
Date: Sunday, 15 February
Venue: Ricoh Arena, Coventry
Kick-off: 14:00 GMT
Referee: Greg Garner
Assistant Referees: Nigel Carrick & Ross Campbell
TMO: Trevor Fisher