Sir Alex Ferguson has praised the achievements of his long-time rival Arsene Wenger, who reaches a major milestone on Saturday when his Arsenal team run out for their 1,000th game under his control.
The 64-year-old first took charge of the north London club on October 1, 1996 and the game against Chelsea at Stamford Bridge this weekend brings up four figures for the Frenchman.
Ferguson, who remained at Manchester United for over a quarter of a century, says Wenger's 17 years and counting has given the club 'great stability'.
Wenger has managed the Gunners to three Premier League titles and four FA Cups, the last of these being a penalty shoot-out victory over Manchester United in the 2005 final at the Millennium Stadium in Cardiff.
Ferguson, who at times clashed with Wenger over the years, said in a statement: "I congratulate Arsene in reaching this momentous landmark.
"Having also reached the same milestone at one club, I cannot emphasise enough the level of dedication, resilience as well as sacrifice required and for that I have for the utmost admiration.
"Over the years we enjoyed some fantastic battles and you could say we had survived together and respected each other's efforts to play good football.
"I always enjoy watching Arsene's sides - Arsenal play the right way.
"Playing against them always presented special challenges that I burned many hours over the years thinking about.
"He has always been a conscientious member of our trade who makes it his business to help other managers.
"Perhaps the biggest compliment I could give Arsene is that I could never be anything other than competitive with my rival for 17 years.
"Overall, this achievement once again shows what stability can bring to a football club and without doubt he has created a permanent legacy during his 1,000 matches with the club."
Chairman of the League Managers' Association (LMA), Howard Wilkinson, added: "David Dein's decision to recommend this relative unknown to the Arsenal board in September 1996 was a stroke of genius.
"I salute Arsene on his extraordinary level of performance and all that he has brought to our game.
"Doing things the right way can be rewarded by sustained achievement at the highest level both on and off the field of play."
And LMA chief executive Richard Bevan said: "Arsene is rightly renowned as a true footballing innovator, not just in England but worldwide.
"This achievement is a remarkable celebration of success and longevity. In a profession where time can often be an all too rare commodity, 1,000 matches at one club exhibits an enduring quality.
"This can only serve as an inspiration to all current as well as all aspiring managers and coaches."
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