West Ham did Arsenal a favor when it beat Manchester United in its last Premier League match and now the Gunners want another on New Year's Day.
West Ham visits Emirates Stadium on Tuesday, just three days after a 2-1 win over United let Arsenal slip into first place.
If Arsenal's luck holds, the Hammers will be exhausted from their weekend exertions.
Things are already looking good for Arsenal, with West Ham's Nolberto Solano and Scott Parker struggling to get fit after being substituted against United because of injuries. Solano damaged his hamstring and Parker hurt his knee.
"We didn't want to take any more chances with it but we are struggling," West Ham manager Alan Curbishley said. "The boys that have perhaps got a chance of coming back in the next few weeks probably won't be ready for that.
"We have just got to get on with it."
West Ham beat Arsenal 1-0 home and away last season, and did the same to Manchester United as it narrowly avoided relegation, but has already lost 1-0 to the Gunners at Upton Park this time around.
The club has been hit by injuries all season, with key players including Dean Ashton, Fredrik Ljungberg and Julien Faubert all missing for long spells.
Anton Ferdinand scored as a second-half substitute Saturday and could start in central defense alongside Matthew Upson, who headed in the winning goal.
Curbishley will likely play just one striker again, leaving him to choose between Carlton Cole and Ashton.
Arsenal was rattled by West Ham last season, with normally placid coach Arsene Wenger getting embroiled in a touchline confrontation with then-Hammers manager Alan Pardew.
However, the brisk passing and tough tackling that unsettled Arsenal then has proved less successful when teams have employed it this season.
In-form Everton was the latest team to try it and led 1-0 at halftime Saturday before losing 4-1.
"Maybe 18 months ago we would be beaten easily but we have had practice in this kind of game," Wenger said. "Today we are less in danger."
United's attempt to rally from its surprise loss at West Ham should be boosted by the return from illness of striker Wayne Rooney and midfielder Michael Carrick.
A virus ruled the pair out of the game at Upton Park, in which Cristiano Ronaldo scored and missed a penalty kick before West Ham's two late goals _ both headers from free kicks.
"Ronaldo missed his penalty but that can happen," United midfielder Darren Fletcher said. "It's not him to blame. He's been fantastic for us and won us many games and many points. We were still in a winning position, so it's nothing to do with the penalty that lost us the game today.
"It was individual errors at set-pieces that have cost us."
Fletcher may make way for Carrick, while Rooney could replace Louis Saha up front and link up with Ronaldo, who leads Premier League scoring with 13 goals.
United trails Arsenal by just two points, so could even retake the lead if the Gunners only draw.
Third-place Chelsea is at west London rival Fulham, while fourth-place Liverpool, which drew 0-0 at Manchester City on Sunday, isn't in action until Wednesday, when it hosts lowly Wigan.
Tottenham looks to continue the form that has brought 11 goals in two matches when it visits Aston Villa in another of Tuesday's matches, while Everton is at Middlesbrough, and Portsmouth is at Reading.
Wednesday has another three matches, with Manchester City at Newcastle, Derby at Bolton, and Sunderland at Blackburn.