"In this day and age with film, hitters see your tendencies and how many changeups you throw a game, if you use it a lot, if you don't use it a lot," Marquis said. "I know a lot of pitchers feel that hitters are getting an edge in terms of patterns and what pitches you're throwing. It's a little something else to have. Instead of working on it during the season, this is a great time to work on it."
Wagner has been experimenting with a combination split-finger changeup.
"From what I understand, that's more like a 'fosh' ball," Marquis said. "You split the fingers and keep three fingers on one side of the ball, so it's not a true split and it's not a true changeup."
Supposedly, Wagner's pitch goes sideways.
"Every pitcher has different arm angles," Marquis said. "The way it comes out of your hand, obviously that's all it depends on. I've messed around with it and I like the way it feels. It has more of a split-like action with changeup speed. Even if it doesn't have the action you want, the velocity change reacts almost like a changeup, so you can have a chance to fool the hitters and get them out on their front foot.
"People sometimes have had trouble with the feel of a changeup and the feel of a split," he said. "There are variations on a grip that people fool around with to find something comfortable."
Marquis said he considered adding a split-finger pitch after 2004 when he lost his "swing and miss pitch" for a stretch.
"I feel like I'm getting that feel back of a good slider, which would be my out pitch with two strikes," he said. "I worked on the split the last two months of last season and all offseason. I always have that in my bag of tricks."
Hitters probably know that. Some of the experimenting could be simply to play mind games with them.
"I learned from a lot of guys that you're better off getting real consistent with three main pitches than having five, six pitches that are average pitches," Marquis said. "Obviously, my main focus is sinker down in the zone, get ahead with that and come up with a breaking ball that I can throw for strikes at any time."
Cubs reliever Bob Howry has played with different grips, and says he experimented with a changeup for a few years, and has tried to add a split the last couple seasons.
"Unless it's something you can pick up and make effective, you stick with what works," Howry said.
Rivera has been incredibly successful as the closer for the New York Yankees with his cut fastball. Adding a changeup could help. Or it could just be a ploy to get hitters to think he has something else in his arsenal.
"That's a possibility," Howry said. "But I guarantee you that when a hitter goes up there against Rivera, he's not going to be looking for a changeup from him."
Maybe not. But Cubs second baseman Mark DeRosa, who admits he's a video guy, watched Seattle's Miguel Batista warm up the other day, and noticed his last two pitches were split-finger pitches. He filed that away when he went to the plate.
"To know he has that pitch in his back pocket, it gets you thinking," DeRosa said.
He agreed with Howry that Rivera doesn't need another pitch.
"Last year, I faced him four, five times and he threw me a couple two-seam fastballs and that totally surprised me," DeRosa said. "You're up there sitting on the cutter, you're sitting on a pitch you can't do anything with, but that's all you can do against him."
DeRosa studies video of opposing pitchers, and tries to find hitters who are comparable to him. He's trying to pick up tendencies, to see how the pitcher approaches the batter in certain situations.
He understands why pitchers are expanding their repertoire.
"It's smart, even if they don't use it," DeRosa said. "All you have to do is show it and the hitter starts thinking about it. From my experience, I usually watch video and study a guy's pitches and try to delete one of his pitches until I get to two strikes. When you're dealing with a guy like Barry Zito, there's no sense swinging at that curveball until you get two strikes, because you won't do much with it anyways."
Carrie Muskat is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.