White Sox reliever Jennings begins using protective inserts in cap

Dan Jennings won't make the same mistake twice.

The Chicago White Sox reliever, who was drilled in the head by a 101-mph line drive off the bat of Pittsburgh's Jordy Mercer last season, has begun using a protective insert in his cap while pitching.

"If it happened again and I wasn't wearing anything, I'd feel pretty stupid," Jennings told ESPN's William Weinbaum.

The 28-year-old saw his 2014 season cut short as he dealt with symptoms of a lingering concussion. He believes that if he was wearing some sort of protective gear when he was struck, it would have made a world of difference.

"Absolutely," Jennings said. "I might have had a headache for a few days, but it's protection in the perfect spot where I was hit."

The new equipment, produced by Safer Sports Technologies, is a 1.6-ounce hard carbon fiber partial insert with Kevlar padding on the side of the head.

The product is already used by Houston Astros pitcher Collin McHugh, though it's different from that of New York Mets reliever Alex Torres.

The equipment Torres uses is an MLB- and MLBPA-approved product - a thick 8-ounce strip of isoBLOX foam padding that surrounds the exterior of the cap.

But despite increased protection for pitchers, the issue stems from a bigger problem. All three MLB pitchers struck in the head this year were hit below the cap line, and there's not much that can be done to protect them.

"I think the only solution to protect the face (and other areas below the cap line) is a full helmet and mask," Jennings said. "But pitchers need to do too much and I don't see how you can pitch that way."