Robbie Keane has admitted that he was losing his motivation for the game as he became a fixture on the Spurs bench.
As the partnership between Jermaine Defoe and Peter Crouch became established the Ireland skipper slipped further and further off the radar.
After being given a 12-minute run replacing Defoe at Birmingham on January 30 Keane realised that he had to move on to salvage his season.
Tonight he'll be given an amazing reception as he makes his home debut for Celtic against Hearts as memories of the Tottenham bench slip into the past.
The new Celtic hero said: "I like to be involved and I love playing. I didn't like to wake up on a Saturday morning knowing that I wouldn't be out on the pitch.At 3pm you're sitting on the bench and it's very difficult to get yourself up for a game.
"I just thrive on playing games and that's why I'm at Celtic. I was delighted to get the 90 minutes under my belt against Kilmarnock.
"I really needed that and the last 20 minutes I was a bit tired, to be honest, but I'm a person who gets better with games.
"The more games I get under my belt the more you'll see a sharper and fitter Robbie Keane.
"I know what I'm capable of doing and I can enjoy my football at Celtic, get my head down and see what happens next season."
Celtic's circumstances don't give Keane any time to bed himself into life at Parkhead with a 10 point gap separating them from leaders Rangers.
An Old Firm derby at the end of this month could make or break Celtic's season after a rollercoaster start to Tony Mowbray's reign.
The former West Brom boss made wholesale changes to the squad last month with Keane convinced that Mowbray's team is developing in the right way.
He added: "The manager is certainly someone who knows his football. He likes to play in the right way.
"I played against his team when I was at Tottenham and he was at West Brom.
"I always liked the way he went about things and the way he played his football.
"The transitional period isn't easy with loads of new players coming in. Things don't happen overnight and it'll take a few games to get it together.
"There's a a big gap to Rangers but there's no question it's do-able. If we can get some wins and good performances then there's no reason why you can't get the confidence back in the team.
"You could see the lack of confidence against Killie. We played well but when we went a goal down it was difficult for the team and we started doing things we normally wouldn't do.
"With confidence you need to step up to the plate and with the players we've got we'll do that.
"By no means is it going to be easy but we've nothing to lose. We might as well go out and give our all and see what happens at the end of the season."