Last Updated: Mon, 25 Jan 2010 16:19
Derek McInnes says there is 'no doubt' the sending off of St Johnstone's Graham Gartland change the game against Celtic.
Saints were 1-0 up following a Liam Craig penalty on 12 minutes, after Steven Milne was fouled in the area, but the course of the match changed when Gartland was dismissed a minute into the second half.
McInnes felt his men were the best team in the first half but the game was turned on its head in the second period, with the Glasgow giants running out 4-1 victors.
The Saints boss said: "Once you went down to 10 men against a team like Celtic it becomes difficult.
"We stemmed the tide for a wee bit and we stretched the game, but they have players who can hurt you on the counter-attack.
"But their goals were great finishes, and we're disappointed with the end result, because my players didn't deserve that."