Josh Wege and six other Marines were driving to a bazaar in Helmand Province, Afghanistan, when their rear left tire tripped the improvised explosive device.
Seated directly above the blast, Wege landed on the ground and felt for his fingers.
He was alive, though he had a broken back and a concussion.
Then he looked at his legs. His right was severed, and he couldn't feel his left.
"I didn't really feel pain," he said, "until I looked."
When Wege began a month-long hospital stay in October 2009 - a double leg amputee at 19 years old - he had a question for doctors.
Could he still play softball?
Growing up in Fond du Lac, Wis., Wege played five nights a week.
"It's a freedom," he said. "If you come from an athletic background, you miss playing a game.
"Especially if your feet are literally taken out from under you."
Wege will get his chance today after the Arizona Wildcats' 6 p.m. game against Baylor at Hillenbrand Stadium.
The exhibition will feature two stand-up amputee squads - the first of its kind - as part of a camp organized by the UA's Disabled Veterans' Reintegration and Education Project.
Twenty men - 17 military veterans, three still active - participated in a three-day softball camp this week.
The group is about half Army, half Marines, with one Navy representative.
Wege is the only camper to lose both legs below the knee.
David Van Sleet, a Veterans Administration Southwest Health Care Prosthetics Manager who is based in Albuquerque, came up with the idea after running a wheelchair basketball camp in Tucson last year.
"They've been missing high-level activity team sports," he said. "A lot of them didn't think they'd ever be on a team again."
A federal grant paid for travel, lodging and food.
Louisville Slugger provided the equipment. Mizuno, with help from UA coach Mike Candrea, provided shoes and uniforms.
"It's just great for us to get a chance to be around some heroes that give us a chance to live in peace," Candrea said. "You don't, sometimes, come in contact with some of the tough stories of people coming back from war. I think this will be an eye-opener for some of our kids."
Kriss Natividad lost his right leg below his knee in November 2008.
Post traumatic stress disorder drove him to drink after returning from the Marines. He drove drunk, hit another intoxicated driver and was pinned against a pine tree for 90 minutes.
"When I first got my leg amputated, it was something I didn't know how to care for," the 30-year-old said. "Maybe here I can learn some tricks and trades to better do things."
Bobby McCardle, a Marine who lost his leg to an IED in Iraq four years ago, said veterans are drawn to the structure of sports.
"I remember in the military, the structure, reveille. … Your body misses it, Your mind misses it," he said.
Van Sleet said he hopes the campers go home and join local leagues. He wants to form a USO Tour team to play overseas and has already booked a game at Walter Reed Army Medical Center in May.
Wege is still based at Walter Reed. He's taken up snowboarding and Olympics-style events since the accident.
"I try to spend my time doing something athletic," he said. "For me, that's the most therapeutic thing I can do."
Games at Hillenbrand Stadium
• Today: Baylor at Arizona, 6 p.m.
• Saturday: Baylor at Arizona, 6 p.m.
• Sunday: Baylor at Arizona, 11 a.m.