ST. PETERSBURG, Fla. » J.A. Happ isn’t sure how he’ll react when gets on a mound again. One thing he does know is that he’s going to try to forget what happened Tuesday night.

Toronto’s 30-year-old left-hander returned to Tropicana Field on Wednesday, less than 24 hours after he was struck on the head by a line drive that sent him to a hospital for an overnight stay.

Happ expects to make a full recovery from a skull fracture behind the left ear that doctors believe will heal on its own, adding he doesn’t anticipate having any fear of returning to work.

"I think you’ve just got to get back out there and try to forget about it," he said. "I won’t know until I’m out there, but I don’t anticipate it being a problem."

He’s not sure when he’ll get the opportunity.

The pitcher sprained his right knee when he dropped to the ground Tuesday night, and that could affect how soon he’ll be ready to pitch again.

Happ realizes his injuries could have been worse.

"I feel really fortunate," he said after limping into the auxiliary clubhouse for a news conference and climbing a couple steps to sit behind a microphone.

"It looks like I moved just a little bit. I don’t remember doing that, but it looks like it was just enough to where it must have caught me in a better spot, because I think it could have got me head on," he said. "I’ve got some stitches and there’s a fracture in the skull, I suppose, behind my ear, but it’s not serious or threatening. We’ll let those heal."

Happ, who was put on the 15-day disabled list, had a brief conversation with Tampa Bay’s Desmond Jennings, who hit the line drive that caught him squarely on the left side of the head. Happ shook hands with several teammates outside the Blue Jays clubhouse while assuring each one: "I’m fine."

"He just wished me the best and hoped for a quick recovery," Happ said. "Obviously, something like that is never intentional. I let him know that I knew that and I appreciated him coming over. It’s a scary thing, I’m sure on his end, too."

When Jennings arrived at the ball park he was relieved to learn from one of the Rays’ trainers that Happ appeared to be OK.

"That enabled me to breathe a little bit," Jennings said. "But you still don’t know until you talk to him, until you see him face to face."

Happ remembers releasing the ball, as well as teammates talking to him while he received medical attention on the field.

"I don’t remember seeing it," he said. "Just immediate loud ringing in my ear. Just pressure on my ear, and I was on the ground. That was kind of it. It took me a few seconds to kind of figure out what was going on, but I do remember them being there … the coaches and Gibby (manager John Gibbons) and obviously the trainers. I was coherent and talking pretty quickly."

He also called his mother while an ambulance was transporting him to nearby Bayfront Medical Center.

"They were holding the phone up to my ear for me. … She was definitely relieved, glad to hear my voice," Happ said.

The hit, still being replayed on TV a day later, left some of his fellow players unsettled.

"I felt horrible yesterday. I played with Happ last year for a little bit," Chicago Cubs pitcher Carlos Villanueva said. "There’s a lot of talk out there about the gear and protective stuff. Hopefully, they’ll come out with something that won’t affect us pitching out there, but it’s still such a fast game. What happens if the ball comes directly at your face? There’s nothing you can do. You can’t pitch with a mask on. It just comes down to the draw of the luck I guess."

Major League Baseball, meantime, is trying to determine the best way to protect pitchers from similar injuries.

The league’s senior vice president, Dan Halem, said a half-dozen companies were designing headgear for pitchers but no product so far was sufficiently protective and comfortable.

"If it doesn’t absorb enough impact, then it may be ineffective," he said.

Dr. Gary Green, MLB’s medical director, said the Head Injury Criterion (HIC) scale is being used to evaluate products and that a cap liner likely would have to be 8 ounces or lighter.

"We’ve found some things that are very lightweight, but they’re not very protective, and then other things that might be protective but they are too heavy and don’t meet the other specifications," he said.

Robert Vito, president of Pennsylvania-based Unequal Technologies Co., said a patent had been submitted for a product he hopes to make available in June. Vito said his employees met with pitchers, coaches and trainers from 26 big league teams during spring training.

"My biggest concern coming from the MLB Players Association is the mirror test. When they put it on, it must be concealed protection that cannot be detected by the fan," he said.

In testing the product, he had someone smash a Louisville Slugger bat into his chest.

"Energy is like water. It’s got to go somewhere," Vito said. "So the energy is either going to go into my body and devastate tissues, tendons and break ribs and crush my heart to where I’m bleeding out internally, or it’s going to get absorbed into the pad and then return some of that energy to the bat, all the while protecting me."

While Unequal has used Kevlar-based products in the past, Georgia-based Evoshield employs "gel-to-shell" technology.

"There is no fast and easy solution," Evoshield CEO Bob Pinckney said in a statement.

Green said an average of two pitchers had been struck on the head by line drives during the past seven or eight seasons.

"While these things are catastrophic, they’re still rare events," he said.

Baseball stepped up its efforts after two pitchers were struck last year. Oakland’s Brandon McCarthy was hit on the head by a liner last September, causing a skull fracture, an epidural hemorrhage and a brain contusion that required surgery. He was released from a hospital six days later.

Detroit’s Doug Fister was struck in the head by a batted ball during the World Series; he was unhurt and stayed in the game.

"I’ve heard a lot of pitchers say they wouldn’t mind trying it. And a lot of pitchers just don’t want it," said Tampa Bay’s David Price, the reigning AL Cy Young Award winner. "So I think the decision would still be left up to that player. If it worked and it didn’t affect anything in the mound, I would definitely look into it."

When a product is available that MLB thinks will provide protection without getting in the way, it will ask the players’ association for its input.

"I guess you’d have to see some prototypes," Happ said. "It would be tough."

In the macho culture of baseball, the adoption of protective gear has been slow. While Cleveland’s Ray Chapman died when he was hit by a pitch in 1920, MLB didn’t make the use of helmets or protective cap inserts mandatory until the National League required them for the 1956 season. Helmets weren’t required until the 1971 season and, even then, they weren’t mandatory for players already in the big leagues.

An earflap on the side of the head facing the pitcher was required for new players starting in 1983. Stronger and slightly heavier carbon-fiber helmets, the Rawlings S100 Pro Comp, were required starting this year.

"You can’t ask a pitcher to use material that he’s not comfortable with. But I’m hopeful that, much like with batting helmets, we’ll figure something out that both allows the players to play without any obstruction but adds to player safety," union head Michael Weiner said. "When they get close to something that they think might work, then at that point we’re both going to look at it together."

Bryce Florie doesn’t see well in his right eye to this day, the result of being struck by a line drive hit by the Yankees’ Ryan Thompson while pitching for Boston in September 2000. Florie returned the following year but ended his career after just seven more big league appearances.

"With the way everything is being condensed, I think it’s inevitable that it’s going to happen, that they’re going to have something in the hat," Florie said. "You’ll have a hard time to get major leaguers and minor leaguers to say, ‘OK, Let me try this out.’ Most of them are not going to want to be the first guy. But if you talk to guys like myself and other guys that have been hit, up in the face, in the head, we’ll be, ‘Like yeah, I’ll do it.’ But then, it’s kind of late."

Goodall reported from St. Petersburg, Fla., and Blum from New York.