The Australian, who succeeded Joe Schmidt in the summer of 2013, led the Irish province to a title defence last season with a win over Glasgow Warriors in the final at the RDS, but a frustrating second season saw Leinster finish outside the top four for the first time since the PRO12 play-offs were introduced.
Matt will leave Leinster Rugby with the best wishes and thanks of all involved with the province for all his hard work during his two years.
O’Connor also led the province to the European semi-finals this season where they were beaten by eventual champions Toulon after 100 minutes of thrilling rugby in the south of France, with the same opposition also coming out on top in the quarter-finals this season .
The announcement was made on Thursday morning by Leinster Rugby chief executive Mick Dawson at UCD followed a meeting of the Professional Games Board, with the club also revealing that forwards coach Leo Cullen will take temporary charge as the search for a successor begins.
Dawson paid tribute to O’Connor for his service to the club without mentioning this season’s poor league form that saw Leinster suffer eight defeats and three draws in their 22 matches – their worst performance in the league since 2003/04.
“During Matt’s time here we won the PRO12 during his first season and have made progress in both European campaigns,” Dawson said.
“Matt will leave Leinster Rugby with the best wishes and thanks of all involved with the province for all his hard work during his two years.
“We wish Matt the very best of luck for the future and thank him sincerely for his contribution to Leinster.”
It is unusual for a coach in Ireland not to see out his contract, but for O’Connor it was a case of too much of a drop off from the glory days of his predecessor, who has since led Ireland to back-to-back RBS 6 Nations wins with a squad made up of many of Leinster’s big names.
We set high standards for ourselves and, for many reasons, we did not achieve those highs throughout the league this campaign.
The loss of Brian O’Driscoll from Leinster’s midfield following his retirement last summer proved to be a problem for much of the season, while injuries, selection decisions and some very poor defensive play too often compounded matters at key moments.
There was an inevitability that he would not enter the third year of his contract when defeats to Newport Gwent Dragons and Ulster ultimately sealed the province’s fate, eventually finishing seven points outside the top four.
A recent benchmark for many clubs in Europe, the realisation for many at the province will surely be that while others have started to catch up Leinster have become stagnate.
While O’Connor admitted that he is disappointed with Leinster’s form in the PRO12, privately he will be more disappointed that he could not build on their resounding win over the Warriors in last year’s PRO12 final.
“I am disappointed and frustrated with our form in the PRO12 this season,” O’Connor said.
“We set high standards for ourselves and, for many reasons, we did not achieve those highs throughout the league this campaign.
“However the European journey that we took over two seasons, for a new group of coaches, players and staff, is one that we can be very proud of.
“The dynamic in Europe has changed with meritocracy and fewer teams competing and this has improved the quality.
“We went toe-to-toe with the best and there is no shame in losing to Toulon by the smallest of margins, and I’m extremely proud of the group and the character shown.”
Panasonic Wild Knights head coach Robbie Deans has been installed as the odds-on favourite at 1/5 by to succeed O’Connor.
The 55-year-old former Crusaders and Australia head coach will be in the UK Ireland over the next two weeks as he leads the Barbarians against Ireland at Thomond Park and an England XV at Twickenham.
Other early contenders for the role also come from the southern hemisphere with another former Wallabies coach in Ewen McKenzie, who has been out of work since November, while Ireland assistant coach Les Kiss, who is inked in to take up the director of rugby role at Ulster after the Rugby World Cup, joins McKenzie at 15/2.
The leading Irishman, according to Paddy Power, was Saracens director of rugby Mark McCall at 9/1, but he has since moved out to 16/1 with Harlequins director of rugby Conor O’Shea as neither are likely to be tempted away from their Aviva Premiership clubs.
At 25/1, former Leinster and Ireland full-back Girvan Dempsey is the first Irishman on the list currently working in Ireland.
While the Leinster Academy coach would be seen as a logical choice to take the reins he could be seen as lacking the coaching experience to return the province to success in the short term.
Former Leinster talisman O’Driscoll has suggested on Twitter that his followers would be better off taking a punt on fictional character Ross O’Carroll-Kelly.
— Brian O'Driscoll (@BrianODriscoll) May 21, 2015
The bookies’ longlist also includes plenty of other non-runners, including All Blacks boss Steve Hansen and highly-rated Chiefs head coach Dave Rennie, who recently agreed a new two-year deal with the Super Rugby franchise.
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