"First and foremost, I'm both proud and delighted to reach this landmark. To get an opportunity to play for my home province, in the city where I was born, is something that I will always cherish. "A lot of the good times that I have had would relate to the camaraderie with my team-mates, some of whom like Victor Costello, Reggie Corrigan and more recently Denis Hickie have moved on," Gleeson said.
"We won the inaugural Celtic League title in my first year as a Leinster player in 2001/02 and since then we've had a lot of success in Europe without taking the next step.
"I'm not usually one to dwell on the past, but I really enjoyed the season before last coming back, as I was, from a bad injury. We enjoyed some great success by beating both Bath and Toulouse in Europe and came close to winning the league."
The 31-year-old added: "It was good to get the first win of the season against Edinburgh last weekend. What's clear is that there are points and places up for grabs and looking at other results in the Magners League, it looks as though every team is in with a shout of winning the title.
"We've another huge test against Cardiff this weekend. They have made a solid start to the season and have great depth in their panel. We haven't had the best of times in Wales in recent years but we did win in Newport against the Dragons towards the end of last year, so that will give us a boost. We know that we'll need to fight tooth and nail to get a result, but weâ00re extremely motivated to improve all facets of our play."
For the trip to Cardiff, Leinster coach Michael Cheika has made changes in the backs and forwards, with cheekbone injury victim Michael Berne losing his place at outside centre to debutant Fergus McFadden.
In the pack, summer signings Stephen Knoop and Shane Jennings will make their first starts of the competitive season, while Kevin McLaughlin also gets the nod at blindside flanker.
The Ireland-capped Leo Cullen will again captain the province, having successfully skippered them to a 23-8 victory over Edinburgh at the RDS last weekend. Meanwhile, a vacancy has been left at replacement prop which will be confirmed closer to kick-off.
LEINSTER: Rob Kearney; Gary Brown, Fergus McFadden, Christian Warner, Luke Fitzgerald; Jonathan Sexton, Chris Whitaker; Stan Wright, Bernard Jackman, Stephen Knoop, Trevor Hogan, Leo Cullen (capt), Kevin McLaughlin, Shane Jennings, Jamie Heaslip.
Replacements: Brian Blaney, Cian Healy/Juan Francisco Gomez, Cameron Jowitt, Stephen Keogh, Keith Gleeson, Cillian Willis, Ross McCarron.