West Ham are likely to field a weakened team in the FA Cup fifth round on Monday.
And that could give Championship side Burnley the chance of an upset at Upton Park.
With the Hammers locked in a relegation battle, manager Avram Grant is unlikely to risk influential players in the last 16 tie.
Captain Scott Parker, as well as the likes of Matthew Upson, Wayne Bridge and Demba Ba, could be benched.
Robbie Keane is out injured, but Germany international Thomas Hitzlsperger is in line to make his debut after a long spell on the sidelines.
Grant steered Portsmouth to the FA Cup final last year, but said on Friday that English Premier League survival for West Ham must come first.
“The FA Cup is always exciting,” he said.
“After a few games you can be in the quarter-finals and semi-finals.”
“I like the FA Cup, but of course our first priority is the league like every other team in the league.”
“It’s a good competition. I like this competition. It gives you a break from the league which is also good.”
“It’s always good to play at home but I know this won’t be an easy game. This team [Burnley], for them the FA Cup is everything.”
“This is an opportunity for them to get everyone to love them and I know from the past that teams can come from the Championship and give it their all. We will prepare ourselves for a very difficult game.”
With eight days between the 3-3 draw at West Bromwich Albion and the clash with Burnley, Grant used the break for a team-bonding exercise.
“It was good for the team spirit and was very successful,” said Grant, whose side have won nine consecutive cup games against lower league opposition.
“We did go-karting and many other things. It was nice. It doesn’t matter who won, but it was nice to watch them enjoy themselves in the middle of everything.”
Burnley, relegated from the EPL last season, are chasing promotion and face a fixture pile-up, but boss Eddie How is taking the game seriously.
“We’d love to continue the run and go as far as we can,” he said.
“We’ll look to enjoy it. I don’t think we’ve got an awful lot to lose.
“We want to go there and put on a performance against a Premier League club who, despite their league position, are a good Premier League club.
“I think it’s a nice distraction and a different kind of pressure with the cup games, it’s probably a nice release for us.”
“We’ll look to enjoy it. I don’t think we’ve got an awful lot to lose.”