He was the Tampa Bay Buccaneers' fourth overall pick in the 2007 draft. The choice was ultimately criticized, along with Adams, who had both his ability and his passion questioned, pretty much a double whammy.
Tampa's new general manager Mark Dominik was credited -- in perhaps the only good thing fans ever said about Dominik -- for salvaging a second-round pick out of the deal, which is what the Bucs got in return for Adams when they traded him to the Chicago Bears in October 2009.
Bears general manager Jerry Angelo was quickly vilified for the trade, particularly when it became apparent Adams had evidently not impressed coaches enough to get on the field for more than a few plays per game, if at all.
On Sunday, Adams became the latest active NFL player to die, and that was his sad and brief epitaph. Disappointing.
We never really knew him here. It appears, from the short statement on Adams' death, neither did the Bears.
"We are stunned and saddened by the news of Gaines' passing," the statement read. "Our prayers are with his family during this difficult time."
The preliminary autopsy report indicated that Adams had an enlarged heart and died of cardiac arrest. Marcia Kelley-Clark, chief deputy coroner for Greenwood County, S.C., told ESPN that Adams' relatives were not aware of any medical condition.
Drug use was not suspected, but toxicology results will probably not be available for at least two months, Kelly-Clark said.
Sadly, when anyone dies so young and so suddenly, there are going to be questions asked and answers demanded. Sad as well are the many things we never got to know about Adams simply because his play had not yet warranted a closer look.
Like the fact that he was a father and a great family man who quietly helped his college teammate, Ray Ray McElrathbey, the Clemson running back who was raising his then-11-year-old brother on his own.
The NCAA relaxed its rules allowing extra monetary aid for McElrathbey and his brother, Fahmarr. But before that, it was Adams who helped organize a few teammates to give the boy rides to and from school, and who took young Fahmarr to the store to buy him school supplies.
Adams was an All-American at Clemson and yes, he was blessed with gifts that showed in flashes of freakish athleticism, but he also made it to that point because of his passion, succeeding against the odds considering his roots in eight-man football in Greenwood, S.C.
"Oh man, the kid was unbelievable," said Ron West, who recruited Adams out of high school and was his position coach at Clemson.
"He played wideout at Cambridge Academy, then went to Fork Union Prep to get his academics in order, and that's where he put his hand on the ground for the first time [as a defensive end]. A friend of mine coached him there and called me and said, 'Uh, Ron, I have a kid here I think you're going to like.'"
West saw Adams -- at a skinny 215 pounds -- come off the ball once and told Clemson they were going to like the kid, too.
The thing that puzzles and annoys West is the notion that Adams lacked passion.
"He was just a kid who developed," said West, who is now an assistant coach at Tulsa. "We redshirted him the first year. He gained weight, got stronger, started playing the next year and he got bigger and bigger and better and better. You don't break every record he could break at Clemson and lead the ACC in sacks like he did without passion."
Monte Kiffin, the Tampa defensive coordinator at the time, was looking for a player who could play 9 technique, on the edge outside of the tight end, and targeted Adams. The Bucs, thinking they had a sack machine -- perhaps the next Simeon Rice -- signed him to a six-year deal worth $46 million, with $18.6 million guaranteed. He fit in well during his first two seasons under Kiffin, even making the 2007 All-Rookie team.
In 2008, in a game against the Bears, Adams had his first career interception and returned it for his first career touchdown in a Bucs overtime victory in the third week of the season. The next week, he had another interception that sealed a victory over the Green Bay Packers.
What the Bucs saw was a soft-spoken, good-hearted kid who did his best and wanted to succeed. He was not a particularly "high-motor guy," but he was never a problem in the locker room. But what they also saw was a player who had no repertoire, no moves and, worse, no countermoves.
"They pick that up very quickly in the NFL and just steer you outside," said one observer of Adams' years in Tampa. "He was a one-trick pony."
As Kiffin packed to leave that year for his new job in Tennessee, he predicted that the next season would be a make-or-break year for Adams.
"But he's a great kid," said Kiffin, an addendum he would use to finish many of his comments about Adams.
In training camp that fall, Bucs coach Raheem Morris publicly called Adams out, telling him and reporters that the player would be considered a "bust" if he didn't reach double-digit sack numbers.
After arriving in Chicago, Adams told West he was fine. And even as Adams was not getting on the field, Bears defensive line coach Rod Marinelli told media and friends alike that he just wanted a year with the kid, that he was still confident he could get it out of him.
"His best years were ahead of him," West said. "It took him a while to develop in college. He worked his tail off to graduate, and he got his degree before he left Clemson because he promised his mom that he would. What I'm telling you is there weren't many like him. I feel fortunate I had the chance to recruit and coach him. He was a tremendous person and a good worker."
At 26, this is what Gaines Adams was left with: warm words from people who knew him, countered by cold numbers on an NFL stat sheet.
I'll take the warm words.
"I admired Gaines' work ethic and how much he demanded out of himself," Bucs defensive end Stylez White told Tampa Bay Online on Sunday. "I didn't know much about his personal life. I didn't have to because he had pictures of his kids all over his locker. That's what kind of man he was. Gaines would, at the time, take his son out of school for three days or so to spend time with him during the season. The reason is because his son lived in another state. He missed him that much."
Melissa Isaacson is a columnist for ESPNChicago.com