Darren O'Dea has signed a new three-year deal with Celtic but has joined Reading on loan until January, the club announced on Tuesday.
The Irish defender has already made 50 competitive appearances for the club since his debut against St Mirren in September 2006.
O'Dea, 22, however, has asked to go out on loan until the turn of the year and has joined the Championship side in a loan deal.
O'Dea is determined to use his loan spell in England to gain the experience that he feels has prevented him from becoming a permanent first-team fixture at Parkhead.
"It's obviously great to sign a new deal but it's more important that I get out now and play football," he told the club's official website.
"This is a massive chance for me to go and play for a good club like Reading and prove my worth and then come back here and obviously try and do the same here.
"Brendan Rodgers, who is the manager at Reading, had tried to get me before when he was at Watford, and I know a lot about him. I've spoken to him and he's a great manager.
"I also know a couple of the Irish lads down there as well and they've had nothing but good things to say.
"So I know what I'm going into and I'm looking forward to getting started. I feel this is the right thing for me to do now - to play first-team football - and when I come back I never want to hear the word 'experience' said to me again.
"If I'm good enough to play here - and I think I am - this is the club I want to play for."
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