Eyebrows were raised in 1977 when Tottenham allowed their goalkeeper Pat Jennings to move to arch-rivals Arsenal.

The Northern Ireland international had spent 13 years at White Hart Lane, playing 591 games for the club and helping them to win the FA Cup in 1967, the League Cup in 1971 and 1973 and the Uefa Cup in 1972.

But, at the age of 32, the Lilywhites questioned his longevity and he was allowed to join the Gunners – a decision that looked rather foolish eight years later when he was still between the sticks at Highbury, having made 327 appearances for their north London rivals.

Indeed, Jennings kept going for so long that he was in goal for his country at the 1986 World Cup, playing the final group game – and his last international match - against Brazil on his 41st birthday.

It has now been 38 years since Jennings’ move across London, but he can see some parallels with Petr Cech’s surprising £10million transfer from champions Chelsea to Arsenal this summer – and he has praised the 33-year-old’s decision as his former clubs prepare to go head to head in Sunday’s north London derby at the Emirates.

“I’ve nothing but admiration for him because he could have quite easily stayed on at Chelsea and just lived on what he had already achieved in the game,” said Jennings.

“I think most people would have been delighted to have done half of what he’s done in his career, and he’s showed just what he’s made of really - the fact that he’s not happy there, bowing out the way he would have done at Chelsea. He’s had the bravery to go on to play for a club like Arsenal.

“He’s done brilliantly in the games he’s played. Going back to the home game against Bayern Munich, even early on he made three or four absolutely brilliant saves, and those saves in the end allowed Arsenal to win the match.

“Chelsea obviously thought he was past his best, and it was a similar thing when I left Tottenham. The managers make those decisions and that’s it.

“From Chelsea’s point of view they got a lot of money for Cech that possibly they wouldn’t have got a couple of years further down the line.

“I think that’s the situation for a lot of goalkeepers. When you look at the ones who were around when I played, we were always written off at 32 or 33. But I was playing in the World Cup at 41 so it just shows that you if you look after yourself you can still carry on without a problem.”

Cech – who was Arsenal’s only summer signing this year – has immediately added weight to the suggestions at the start of the season that his arrival could be a key factor in re-establishing Arsenal as genuine title contenders.

Meanwhile, France captain Hugo Lloris is a central figure in a Tottenham squad that is starting to dream about Champions League qualification again, producing consistently impressive performances in goal while also captaining the side.

“They’re both brilliant,” said Jennings. “Hugo’s been absolutely brilliant for us. I don’t know how many points he’s saved us but he’s made unbelievable saves in every game.

“[In terms of Tottenham’s best goalkeepers], Ray Clemence did a brilliant job as well - what he’s achieved speaks for itself - but Hugo’s right there. You’d just be so happy to have someone like Hugo there behind you every week.

“It’s his reading of the game, his agility. He just reads situations and he’s got great experience as well, playing at the highest level every year with France.

“He’s a really lovely, down-to-earth guy. He doesn’t get carried away. As goalkeepers you don’t get carried away with any situations. One minute you’re on a high and you make an unbelievable save, and then the next minute you’re on the floor, so you’ve got to keep your feet on the ground.”

Jennings won medals with both Tottenham and Arsenal but, as his former sides gear up for Sunday’s derby, there is no doubt who he is cheering for.

“Tottenham’s my club, there’s no doubt about that,” he said. “I’ve been there now on the coaching side for 22 years and I spent 13 years there as a player, so there’s no doubt where my loyalties lie. I’m Tottenham through and through.

“Having said that, everywhere I go I’ve never had a bad word to say about Arsenal – how could I? My home team Tottenham put me out to grass and sold me after 13 years and the club up the road gave me two four-year contracts. How could I ever have a bad word to say about them?”

Jennings – who now has his own lounge at White Hart Lane - has been involved with goalkeeping coaching at Spurs ever since Ossie Ardiles took charge in 1993, and his expertise and experience is still proving to be valuable in the academy.

He has assisted the development of 20-year-old Luke McGee, who signed a new four-year contract last week, and was at Stevenage on Tuesday night to watch the Under-21s take on Schalke in the group stage of the Premier League Under-21 International Cup.

“It’s nice to be able to go and chat with the young goalkeepers,” he said. “You’ve seen them play in matches and the coaches don’t tend to see the same problems as we see for goalkeepers, so we can tell them these situations and I would think there’s no doubt it helps them a lot. I love it, I really enjoy it.”

Follow me on Twitter @BenPearceSpurs