Celtic's Champions League hopes suffered a blow yesterday as captain Scott Brown's appeal against the length of his suspension was dismissed by UEFA.
The midfielder was banned for two matches on top of his automatic one-game suspension for being sent off in the Group H clash against Barcelona on October 1, when he flicked a leg out at Neymar after fouling the Brazilian.
Brown missed the home game against Ajax as a result and travelled to Geneva to plead his case to UEFA's appeals committee, eager for the chance to return early.
However, that appeal was unsuccessful and the Scotland international will sit out the return game against Ajax in Amsterdam next Wednesday night and the visit of AC Milan later in the month.
Celtic manager Lennon, speaking ahead of today's Scottish Premiership clash with Dundee United at Parkhead, said: "It has been turned down. We didn't win the appeal. It is disappointing because we thought we had a good case.
"He will be flying back and meeting up with the squad tonight. I feel the ban is excessive for a misdemeanour, or whatever you want to call it.
"I am sure we had a fair hearing, but it wasn't to be. It is a blow for us and for Scott and we will just have to deal with it."
With midfielder Nir Biton suspended for the trip to Holland after being sent off in the 2-1 win against Ajax, Joe Ledley having problems with his back and Kris Commons racing to overcome a hamstring injury, Lennon pinpointed the importance of Beram Kayal as he pondered his line-up for the visit of United.
Former Celtic skipper Lennon said: "We will have to keep an eye on Kayal, we can't afford to lose too many players in that area."
Lennon, who addressed reports that he is interested in Partick Thistle left-back Aaron Taylor-Sinclair by saying "it is just speculation at the minute", is looking to remain unbeaten in the league before setting off for Amsterdam on Tuesday.
"I want to keep this run going, I want to go into the Ajax game in good shape, psychologically," he said.