
The fans are already more than restless following the departure of the popular Jose Mourinho and the situation has not been helped by the fact that former Israel manager Avram Grant, untried at this level, has replaced the charismatic Portuguese manager.
Grant has had a less than auspicious start, losing his first match in charge away to champions Manchester United, followed by a victory over lower league Hull in the Carling Cup before drawing with Fulham at the weekend.
Chelsea captain John Terry had an operation Sunday on a depressed fracture of his cheekbone picked up in that match but will start the Group B encounter against Valencia.
The centre-back suffered the injury in a clash with Fulham's Clint Dempsey Saturday, and had surgery the following day, and it had been feared he could be out for several weeks.
But Terry has been cleared to play after club doctor Bryan English created a special mask to protect the injury.
However, midfielder Michael Ballack misses out with an ankle injury while Frank Lampard and defender Ricardo Carvalho are unlikely to be quite ready as they continue their comebacks from injury.
Striker Didier Drogba has recovered from a knee injury, started and was sent off against Fulham on Saturday, and should play.
Meanwhile, Valencia are still without left-sided players Edu, Vicente Rodriguez and Jaime Gavilan, though ageless keeper Santiago Canizares could well be fit to return, sending Timo Hildebrand back onto the substitutes' bench.
Valencia have won their last six games by one goal, including their 1-0 win away to Schalke 04 in their opening group match. Chelsea could only manage a draw against Rosenborg, who take on Schalke, in their opening group match.
In Group A, last year's beaten finalists Liverpool play host to Marseille with virtually a full squad apart from the long-term absentees Xabi Alonso and Daniel Agger.
Manager Rafa Benitez welcomes back midfielder Javier Mascherano but Jermaine Pennant is suspended following the red card he picked up in the 1-1 draw against FC Porto.
Real Madrid also have their injury problems ahead of Wednesday's Group C match away to Lazio.
Star striker Ruud Van Nistelrooy has missed the last three matches with a pulled muscle. Defenders Michel Salgado, Christoph Metzelder and Pepe all missed Sunday's 1-0 win away to Getafe, and are all doubtful for Wednesday.
Robinho and Fabio Cannavaro are also both doubtful after picking up heavy knocks at the weekend.
Lazio's mainstay striker Tommaso Rocchi hurt his ankle at the weekend and will miss the game against Real, who are top of the group after beating Werder Bremen 2-1 in their first game. Bremen take on Olympiakos in the other group game.
In Group D, reigning champions AC Milan visit Scottish champions Celtic after yet another dismal showing in the home league.
A 1-1 home draw with Catania left Milan seven points adrift of leaders Inter Milan after six games.
"We are going through a bad patch," admitted coach Carlo Ancelotti. "We are slow, lacking concentration and careless."
Ancelotti will be without injured centre-back Kakha Kaladze for the trip to Glasgow.
DPA