McDonald took exception to being replaced on Saturday

Celtic striker Scott McDonald insists he is "150%" behind manager Gordon Strachan despite throwing a tantrum on being substituted against Motherwell.

"No player is happy coming off when the game is in the balance but in saying that, my reaction was totally incorrect," said the Australian.

"I apologised to my team-mates and manager straight after the incident and then again in the changing room.

"I'm 150% behind my manager and everyone at the club."

Interview: Celtic player Scott McDonald

Celtic's top scorer was replaced by Georgios Samaras on the hour as Motherwell held on for a 1-0 win in Glasgow.

Amid a chorus of boos, McDonald showed his own feelings as he threw his tracksuit top away in anger before kicking out at a dug-out seat.

"It was nothing to do with the team or the gaffer, it was just my passion for playing for the club," said McDonald.

"I wanted to stay out and try and turn the game around for the team and myself.

"He (Strachan) made the decision for the team and I've got to understand that.

"I'm part of that team and when you do what I did it creates a negative reaction all round the stadium.

"That was incorrect for me. We are all in it together and you have to get behind the 11 players who are on the park at that time.

"I put my hand up and apologised for what some people would call my petulance.

"Credit to the gaffer and the way he dealt with it. We continue to work together and we go forward from there.

"It's not the first time you've seen this from a player and I'm sure it won't be the last."