Terry has a back injury that might keep him out of central defense and the midfield could be missing Lampard, who is struggling with a calf problem.
"We've got three days to check them and take a decision on the game," Chelsea manager Carlo Ancelotti said Friday. "We have more possibilities with John Terry. Lampard, I really don't know if he's available or not."
Chelsea is still trying to get its title defense back on track following the club's worst run in the league for almost 15 years.
A victory over Blackburn last weekend ended a two-game run without a win. The Blues, though, have not won consecutive league matches since the end of October, when they last won away and also had a five-point lead.
Since then, Manchester United and Manchester City have taken over the lead in the title race, ahead of Arsenal and Chelsea.
"This is the reason we've lost our position in the table," Ancelotti said. "When we deserved to win - against Birmingham, Tottenham ... we were a bit unlucky.
"We had a lot of chances at Birmingham to score, and we missed a penalty at the end of the game against Tottenham. Those performances weren't so bad, but the results were obviously no good."
Chelsea's collapse has coincided with Arsenal's revival, as Arsene Wenger's side chases its first trophy since 2005. As well as the league, the Gunners are still in contention for the Champions League, FA Cup and they face Ipswich in the League Cup semifinals on Tuesday.
Arsenal goes into Saturday's match against Wigan only two points behind Manchester rivals United and City in the title race.
"We have a stronger belief than at the start of the season and our togetherness is better than at the start," Wenger said. "We are on a good run in the championship and every game becomes crucial now.
"We know our home form can make a huge impact on our success, and that's why if it is Wigan (on Saturday) or anybody else at home we want the three points. Everybody has learned since the start of the season that there is no room for taking anybody lightly because everybody can beat everybody in this league."
Except Manchester United - so far.
The 18-time champions, who face Birmingham on Saturday, are unbeaten after 21 matches and on course to emulate Arsenal's "Invincibles" of 2003-04.
"It would be a hell of an achievement," Birmingham manager Alex McLeish said.
"It's ominous, the fact that they've got to this stage unbeaten and their form is probably gathering momentum," McLeish said. "They are probably looking better now than in the earlier part of the season when they had a lot of draws. It's amazing that they are unbeaten and I think that they can only get better."
Liverpool manager Kenny Dalglish needs his side to improve to end the threat of relegation. The Reds, who are just four points above the drop zone, head to Wolves on Saturday having recorded only two away wins in almost 13 months.
"It's surprising, the reasons why have yet to be fathomed," Dalglish said. "It's up to the players to come together and try to turn it around as quickly as we can. It's very unlike Liverpool not to have a good away record. Normally it's excellent. There are some things we've got to put right and that's one of them."
Also Saturday, fifth-place Tottenham is at Newcastle, Blackpool hosts Sunderland, bottom-place West Ham plays at Everton and Stoke heads to Fulham.
In Sunday's only match, Blackburn hosts West Bromwich Albion.
