Dubliner McGinley, who holed the winning putt in the 2002 match at The Belfry, was unveiled as skipper for the 2014 contest at Gleneagles at a press conference in Abu Dhabi.
The 46-year-old was the unanimous choice by the European Tour's Tournament Committee to lead the defence of the trophy on Scottish soil and McIlroy said Europe have the right man for the job.
After the Americans appointing golden oldie Tom Watson as skipper, some had suggested Europe needed to follow suit and give the captain's role to someone with a greater stature than the Irishman
Colin Montgomerie, the Scot who led Europe to Cup glory in 2010, was thrust into the picture but the Europeans have stuck to their guns. McIlroy, who played under McGinley in the 2009 Seve Trophy for GB&I, spearheaded a vocal, online campaign in favour of the four-time European Tour winner.
He said: "I don't mind it being a David and Goliath situation in terms of the captains. It's won on the course, not on the stage.
"Paul deserves it. He has been a great player and a great personality for the European Tour.
"I also played under him at the Seve Trophy in 2009 and he did a great job. Common sense has prevailed."
McGinley, who has won three Ryder Cups as a player and two as a respected vice-captain, welcomed the support from such a big-hitter like Major-winning McIlroy.
He said: "I was fortunate that I had that situation where Rory had played under me and that's why I think he spoke with such authority on the subject. It means a lot,
"If Rory does not make the team, I think he has got a good chance of a pick now."
Meanwhile, Glasgow star Scott Jamieson, a member of McGinley's Seve Trophy side in 2011, expressed his joy at the appointment. He said: "Paul gets my vote. He will be a great Ryder Cup captain."