If Tampa Bay Rays RHP Alex Cobb had enough innings last season to qualify for such things, he would have led the major leagues with the largest percentage of change-ups thrown per start at 33.8 percent.

But in his first start this season, only 18.4 percent of his pitches were change-ups. Cobb is throwing more of what he calls a spike curveball, and the results produced a solid spring and 7 1/3 innings of shutout ball against the visiting Indians in his 2013 debut.

Cobb, who faces the Red Sox tonight at Fenway Park, feels the curveball, which he throws by digging the finger nail of his right index finger into the seam of the baseball, has made a positive impact on his ability to be successful at the big-league level.

“It's huge,” he said. “Not only for a put-away pitch but it's also, on the change-up I relied a lot on swings and misses hoping they chase out of the zone. This curveball allows me to start off the count early with just a get-me-over curveball, and usually they'll take it if it's not the pitch they're looking for. So to be able to get ahead in the count is huge. I wasn't able to do that so much with my change-up. It's more of a hoping they chase kind of a pitch, and this one is more of an out of the zone in the zone.”

Cobb made the switch from the traditional curveball grip last season, learning the spike grip from former Rays James Shields and Wade Davis.

“It took a good half of the season last year where I was only throwing it 74, 76 (miles per hour),” he said. “It was still good. It was good from the first day I started it, but it wasn't as fast as it is now and it wasn't as sharp. I saw success with it right away, but it's gotten a lot better now that I'm more comfortable with it.”

Cobb said he can throw the pitch in the 79- to 82-mph range.

“It keeps a tighter spin,” he said. “More of a four-seam rotation so it's harder to pick up. I've also gained a few miles per hour on it, so it's been a huge help this year.”