West Ham United begin the acid test of their European credentials when they visit Sunderland on Saturday.
The high-flying Londoners are fourth in the table following their 3-1 win over Swansea City and will regain third from Manchester United with victory this weekend.
However, manager Sam Allardyce has insisted that he will not even entertain thoughts of Champions League qualification until after the festive fixtures.
A run of five Premier League games in 19 days, which includes matches against Chelsea and Arsenal, may go a long way to determining whether the Hammers are capable of challenging for a top-four finish.
Firstly, though, comes a trip to Sunderland, who will be hoping to deny United a fourth straight win.
The Black Cats held Liverpool to a goalless stalemate last time out for their fourth draw in five and ninth of the season - no team has had more at the 15-game stage of a Premier League campaign.
Wins have been harder to come by for Gus Poyet's side - they are without one in five - and he will be desperate to start getting more three-point hauls which will send them clear of the relegation zone.
Having freshened up his side for the visit to Anfield, Poyet may restore midfield regulars Lee Cattermole and Jack Rodwell, as well as first-choice forward Steven Fletcher for the game at the Stadium of Light.
Jozy Altidore, Liam Bridcutt and Jordi Gomez are likely to be sacrificed, and Wes Brown may also be dropped now that loanee Sebastian Coates is available again, having been ineligible to face parent club Liverpool.
Connor Wickham, who has previously been a transfer target for the Hammers, finally committed his future to Sunderland this week by penning a new long-term contract and will continue on the left flank.
Allardyce is now blessed with striking options and has a selection dilemma, with Diafra Sakho having marked his return from injury by completing the comeback against Swansea with his seventh goal in nine games.
The Hammers also have Andy Carroll fit and firing again, and the England international is certain to retain his place after ending his eight-month wait for a Premier League goal with two trademark headers.
It could therefore be Enner Valencia who misses out for the visitors, along with the injured Mark Noble. Carl Jenkinson is expected to shake off a knock to continue at right-back, with Joey O'Brien on standby.
Diego Poyet, son of Sunderland boss Gus, has returned from his loan spell at Championship outfit Huddersfield Town and is in West Ham's travelling party, but is unlikely to make the matchday 18.
These two teams played out a 0-0 stalemate at Upton Park on the same weekend of last season.
Sunderland:
Recent form: WDDDLD
Possible starting lineup: Pantilimon; Vergini, Coates, O'Shea, Reveillere; Cattermole, Larsson, Rodwell; Wickham, Johnson, Fletcher
West Ham:
Recent form: DDLWWW
Possible starting lineup: Adrian; Jenkinson, Tomkins, Reid, Cresswell; Song, Kouyate, Nolan; Downing; Carroll, Sakho
Sports Mole says: 1-2
Joe Fish
