SIMON Charlton is leaving the Reebok after four years as one of the mainstays of Sam Allardyce's defence.

The trusted left back signed on Tuesday for Premiership new boys Norwich City in a surprise move, which was completed in the Far East.

Charlton became the Canaries fourth summer signing after flying to Kuala Lumpur overnight to link up with his new team mates on the club's pre-season tour of Malaysia.

The vastly experienced defender, who was Wanderers' player of the year in 2001-02, still had a year of his Reebok contract to run but has joined Norwich on a two-year deal with a one-year option. The initial transfer fee of £250,000 will double if the Canaries survive their first season in the Premiership.

The sale comes just 24 hours after Ricardo Gardner -- Charlton's main rival for the left-back berth -- secured his long-term future by signing a new four-year contract and comes in a close-season in which Allardyce has made no secret of his intention to draft in at least one more left-sided defender.

That he has allowed the 32-year-old to leave now suggests he has a replacement lined up.

Charlton, who was a career left-back until last season when he also impressed as an emergency centre-half, joined Wanderers in July 2000 on a free transfer from Birmingham City. He made his name with his home town club, Huddersfield, before playing more than 100 Premiership games in a four-and-a-half year stint at Southampton.

He leaves Wanderers after making 137 senior appearances, having been a key figure in the club's meteoric rise from Division One, via the play-off success of 2001, to their highest top-flight finish for 44 years.

Norwich manager, Nigel Worthington, said he was signing Charlton for his "wealth of experience".

"Simon's got great energy, great enthusiasm, great knowledge and a great desire to do well at Norwich City," he said.

Allardyce said he could not offer Charlton the security he was looking for. He said: "Simon Charlton has been a great ambassador and servant to Bolton Wanderers and I'd like to wish him well on his move. His contract expires next June and he was looking for a long-term deal, which we weren't prepared to offer him."

The manager hinted that, despite his recent frustrations, more new signings were imminent.

"There is quite a lot of activity behind the scenes," he added. "I am hopeful of one or two signings in the near future, but at this stage we are not prepared to release the names of the players we are talking to."