"Some of my team looked very tired tonight, although we had fresh players so can't use that as an excuse," he added.
"It's possible that we'll pay the penalty of so many games, so we need a bigger, strong squad."
Tigana had no argument with the referees late dismissal of Zat Knight for the tackle which led to Paolo di Canio's last minute winner for the Hammers.
"It was normal that Zat was sent off tonight. He wanted to get the ball but missed it.
"We made the same mistake as against Manchester United - one ball that went between two players."
WEST HAM MATCH REPORT
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