"Coaches would call me and ask me if I had any injuries I should tell them about and as soon as I explained what happened, nobody called again except La Salle," Sheehan said.
He earned a spot on the La Salle University football team in 2007, but suffered another injury and then La Salle discontinued its football program that same year.
He spent most of his undergraduate years as a regular student until the men's basketball team's video coordinator, Terrance Stewart, spotted the then-senior playing pickup basketball with a friend and a cafeteria worker.
"Honestly, it was just a normal game, nothing crazy and the guy we're playing with, who is close to 40 years old, he was taking us to the rim and playing hard 'D' and I didn't think I was playing that well," Sheehan said. "I think it was just perfect timing. I think they were getting ready for the season and thought, 'Maybe we can add one big body,' and then they saw me play and it was just perfect."
Stewart took what he saw back to head coach John Giannini and in the fall of 2010, Sheehan's athletic career got another breath of life as a walk-on.
"We did our research and found out he was an honor student and one of the most respected people on campus," Giannini said. "We found out he was the same way at Episcopal Academy. He was a good athlete, a team guy, a good student and just a good friend and person, so he's exactly what we look for in a walk-on and he's helped us a lot, and we're completely thrilled with him."
Sheehan and the Explorers play host to Richmond in the first round of the Atlantic 10 Tournament tonight. A victory puts the 20-11 Explorers in the quarterfinals on Friday at Atlantic City.
Between the end of his football career and the start of his time with the basketball team, Sheehan excelled in the classroom. Last May, he graduated cum laude with degrees in criminal justice and sociology, and is currently pursuing a graduate degree in education while maintaining a role on the team that does not entail much playing time. In 13 games this season, he has averaged 1.5 minutes.
"There's a lot of kids who walk on thinking they will be a huge part of the team, but you have to know that you're there to be a practice player, you're there to cheer everybody on," Sheehan said. "Not many people want to do all the work and just sit on the bench the whole time, but I love it, I still get pumped up as if I was going to play."
With Sheehan, 6-4, 245, more conditioned for football than basketball, he presented an unusual challenge for his teammates in practice.
"[The other players] respect him tremendously as an athlete because he still has that football strength, he's the strongest guy in the weight room by far," Giannini said. "If it wasn't for his knee surgeries, he could be effective in many other ways, but our guys respect him as an athlete and they really respect him as a person.
"If the guy wanted to, he could body-slam anyone on our roster - this is a strong dude - so the respect is definitely there."
That strength was on display in Sheehan's first practice with the Explorers. While Sheehan was defending forward Ruben Guillandeaux on a fastbreak, the team got its first taste of Sheehan's physical play.
"In high school, I was taught that since I couldn't jump very well, instead of jumping up to try and block the shot, I used to use 'the hammer' and just try to whack the kid as hard as I could at the ball, so if I fouled him, he couldn't get [the shot] up," Sheehan said.
The player nicknamed "Cheddar Bird" dropped "the hammer" on Guillandeaux, sending him tumbling to the floor, unhurt.
"[Coach Giannini] said, 'Bird, if he's done, you're out of here,' and that was the first practice, so I had to change my ways," Sheehan said. "My method of basketball is not the standard."
Sheehan said he thinks his style of play has made the Explorers more prepared for physical games and against players who aren't always on the right side of the rules.
"I'm the guy holding the bag when they go up, and for a tough finish I would be whacking them pretty damn hard," Sheehan said. "I'm tough to box out and I don't necessarily do it the legal way so it should make them more prepared."
In the closing minutes of an 89-51 win over Towson in early December, Sheehan scored the first points of his Explorers career.
"I had the starting point guard on me, which was good because even if he could outjump me, I still had 2 inches on him, so I start backing him in and I got fouled and the and-one, so it was great," Sheehan said.
He would set a career high in scoring with three points in a similar fashion during a 85-59 win over Central Connecticut State, and this time he made a free throw. In another blowout win over Hartford, he tried the same tactic that worked against Towson, backing his opponent down, but this time it failed. Hartford assistant coach Drew Dawson, a Philly native, joked that he had seen Sheehan coming.
"As soon as I got the ball, the kid took a charge," Sheehan said. "The joke was that they scouted me and knew what I was going to do."
When Sheehan is on the court, it's not in a high-pressure situation, but it always creates a stir.
"When I go in, spirits are up because we're up by a lot and as soon as I get the ball they go, 'Shoot it,' even if I'm at halfcourt," Sheehan said. "It helps me out, but it also makes me more nervous than I should be."
Said Giannini: "The guys are so happy for him because he gives so much every day."