Rangers manager Walter Smith refused to use their European schedule as an excuse for capitulating in Sunday's Old Firm derby.
The Scottish champions slumped to a 3-0 defeat at Celtic Park, allowing their rivals to stretch their lead at the top of the Clydesdale Bank Premier League to eight points.
The SPL clash was sandwiched between Thursday's Europa League tie against Sporting Lisbon, which ended in a 1-1 draw at Ibrox, and the return leg in Portugal in a few days time.
But, as far as Smith was concerned, his side simply were not good enough on the day regardless of their other fixtures.
He said: "We played in Champions League games earlier in the season and had to come back and play.
"It doesn't help but it's no excuse overall for the way we played against Celtic."