The Blues suffered a 2-1 defeat by Paris Saint-Germain in the French capital on Tuesday night in the first leg of their Champions League last-16 clash.
Pellegrini’s side begin their knockout-stage campaign with a trip to Dynamo Kyiv three days after their FA Cup clash in west London.
Former Liverpool defender Lawrenson believes there is a good chance the City manager could field a weakened side at Stamford Bridge.
“I was in Paris to watch Chelsea play Paris St-Germain in the Champions League on Tuesday and they played pretty well despite losing the first leg of their last-16 tie,” Lawrenson told BBC Sport.
“Chelsea boss Guus Hiddink might be missing one or two players through injury, but it looks like Manchester City might be missing more for other reasons.
“We are not sure what sort of team their manager Manuel Pellegrini will put out because of how close this game is to their trip to play Dynamo Kiev in the Champions League on Wednesday night.
“Pellegrini says he may field a weakened team at Stamford Bridge. If he does, it will be a shame because it is not great for the FA Cup, but you can understand why.”
Chelsea are in 12th place and 14 points behind fourth-placed City, who occupy the final Champions League qualifying spot.
The Blues are seven-time winners of the FA Cup but haven’t won the competition since beating Liverpool in 2012.
City, meanwhile, haven’t won the competition since 2012 under Roberto Mancini when the cash-rich side beat Stoke City 1-0.
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