There were fears the Chelsea youngster had damaged ligaments, which would have kept him out for weeks, but scans on Wednesday revealed only a sprained ankle - and Mount is now being treated intensively in a bid to get him fit for Sunday's clash.
The Valencia contest follows Saturday's 5-2 Premier League win at Wolves, which saw Chelsea's young academy graduates Fikayo Tomori, Tammy Abraham - scorer of a hat-trick - and Mason Mount all register goals. Battling well to form a defensive rearguard, Parejo and Kondogbia laid the foundations for their second-half performance, cutting through Chelsea's midfield with intricate one-two's to pick off the space. But we are going to win home games.
Meanwhile, Napoli's first goal in their 2-0 win over holders Liverpool came from a dubious spot-kick.
"I'm happy to score and contribute to winning the game, but as a whole I thought we all did well and it was a big night for us".
"We don't know how bad it is", Lampard said. We've got a confident bunch of lads.
However, he has done a good job at rallying his players. We can take our anger out against Liverpool.
Willian, although, confirmed that he wanted to take the penalty, no matter now now not being no 1 or number two on Lampard's list, by pronouncing: "I wanted to take it but he (Barkley) used to be confident to take it".
Lampard, scorer of one of the penalties in the shootout against Bayern in Munich in 2012 when Chelsea memorably won the Champions League for the first and so far only time, said he was looking forward to a return to Europe's elite competition. They've killed everybody on the pitch, started controlling again and then we've conceded a penalty. This is football. He missed the penalty but it could be me that missed, or Jorginho or whoever.
Willian was upset to see Ross Barkley take the penalty, and the English midfielder probably wishes he let someone else take it after missing over the bar.
"I say it loud and clear: It's not fair". But it is a testament to just how brightly he has started this season that his injury against Valencia, inflicted by Francis Coquelin's reckless challenge, came as a considerable blow to manager Frank Lampard.