The Cottagers host Dutch club FC Twente in their opening Europa League group stage match but with Sunday's Premier League fixture with Manchester City in mind, Jol is unsure if the 30-year old can start both.
"He's fully fit, but we've got another game on Sunday, so that is another decision to make," Jol said.
"It could be a problem with the likes of Bobby Zamora - a bit older, maybe not 100% fit.
"Don't forget that we missed Bobby in three league matches as well, so that was a problem.
"If you play in the Europa on a Thursday, you have to play your league games on a Sunday - that is tough.
"And that is why we will change a few positions to keep a few players maybe fitter for Sunday."