When Mike Holmgren agreed to become the President of the Cleveland Browns back in 2010, he called the endeavor his "last great adventure." Two years later and an earlier than anticipated exit on the horizon -- thanks to new Browns owner Jimmy Haslam -- Holmgren may have one more adventure in him after all.Holmgren, who was the head coach in Green Bay and Seattle for a combined 17 seasons (1992-2008), hasn't exactly excelled in his cushy front office role. On Wednesday, Holmgren admitted that he "misses" coaching and might even be interested in a return to the sidelines."I've learned a lot of things the last three years," Holmgren said to a group of reporters in Cleveland. "And one of the things I thought I knew, but now I know is I do miss the coaching part. I really do."Holmgren's time up in the luxury box, overlooking the field, apparently hasn't provided him with the same fire and desire as calling the shots on the sidelines. That's why the Super Bowl XXXI winner is at least considering filling that empty space in his uber-competitive chest with another shot at a title."I'm leaving it open," Holmgren said. "You know I said this was going to be my last great adventure, I thought it was going to be longer. And so, we'll see what happens."If Holmgren were to return to the sidelines, at age 64, he wouldn't even be the oldest coach in the NFL. Tom Coughlin, who just won his second Super Bowl last season, has that honor at the ripe age of 66. Pete Carroll is up there too, believe it or not, at 61. And both Bill Belichick and Mike Shanahan are 60 and still have a number of years left in them before retirement.So a return to the field wouldn't exactly be out of the question for the extremely successful head coach. He'll likely be courted, along with the likes of other former head coaches Bill Cowher and Jon Gruden, this offseason and could land himself a nice gig in Kansas City, Buffalo or even Detroit. But, as Mike Florio of Pro Football Talk noted, the situation would have to be right for Holmgren to even consider a return.Have a question for Luke Hughes? Send it to him via Twitter at @LukeFHughes or send it here.