Olivier Giroud is yet to start a Premier League match this season.
The Frenchman might be on his way out of Stamford Bridge by this January transfer window if he is not given any first-team minutes.
He is third on the pecking order behind summer signing Timo Werner and Tammy Abraham.
He came off the bench five times in the Premier League this season only playing more than 15 minutes on one occasion.
Even France coach Didier Deschamps urged Giroud to sort out his future in order to get more game time in the Euros.
Lampard said: “It’s not a case of giving players reassurances over game time.
“It’s difficult to do. You want players out of the team to train well and perform.
“It gives me nice problems. Oli has always done that as such.
“Particularly after the restart when he was fundamental to us getting into the Champions League spots.
“I’m not going to give my team selection out today.”
He added: “I can’t answer for him but from my point of view I have competition for places.
“Tammy has been scoring and making assists. I can’t give assurances but I never see anything negative from Oli.
“Playing like the other night, clearly he will get plenty of opportunities.”
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