The former Southend and Port Vale forward who was released by Leeds boss Gary McAllister midway through a two-year deal signed last summer, has been snapped up by Town manager Stuart Gray.

The Cobblers boss has been trying all summer to beef up his forward line, and will be delighted with the acquisition of a player with a proven track record in the lower leagues.

"Leon is a centre forward who gives us a physical presence, he is a proven goalscorer at this level, and we are delighted to get him into the football club ," said Gray.

"His goal ratio is very good, and hopefully he can reproduce that for us."

Constantine said: "I am happy to be here. It is nice to come somewhere where you are wanted.

"I have played here on numerous occasions and it is always been a good ground, it is a good club, and I am looking forward to playing here and looking forward to the challenge."

Londoner Constantine is 30 and joins Town after an unsuccessful stint at Elland Road that saw him make just four league appearances and score two goals.

His time in Yorkshire was plagued by injuries, and his season was more or less ended in January when he suffered a broken arm.

He regained fitness in March and went to Oldham on loan, where he scored twice in seven starts, but new Leeds boss McAllister, who never selected Constantine after taking over from Dennis Wise, decided the gangly striker didn't figure in his plans.

Last season was a disappointment, but it was in his spells at Southend and Port Vale when Constantine made his name.

The 6ft 2in front man scored 25 goals for the Shrimpers in 2003-04, before moving on for unproductive spells at Peterborough and Torquay, who paid £75,000 for him.

He was snapped up on a free by Vale in 2005 and was a regular scorer, rattling in 38 goals in two seasons, a run of form that won him his move to Leeds last summer.

But the Elland Road switch was to prove a flop, with injuries meaning he didn't score his first league goal for the club until New Year's Day against Oldham – and he promptly broke his arm in the same game.

Constantine has scored at Sixfields and against the Cobblers just once in his career, rattling in a penalty for Southend in a 2-2 draw in April, 2004.