Nationals Spring Training: Matt Williams Talks Felipe Rivero, Ross Detwiler's Cutter

Having just watched prospects like 25-year-old lefty Sammy Solis and 23-year-old left-hander Matt Purke throw live BP, Washington Nationals' Manager Matt Williams talked to reporters on Saturday about the pitching depth the Nats have in camp this spring competing for roster spots. "Lots of potential big league arms," Williams said. "It's a great problem to have I guess when you've got that many, but that's just a credit to scouting, drafting and development. There's a lot of guys that are on the verge of being ready. That's good."

General Manager Mike Rizzo talked about the success Nathan Karns had in the organization as a success story for the Nationals' scouts and player development people too.

Karns' return from shoulder surgery and the work he did at Double-A last season, made him an attractive target for the Tampa Bay Rays, who dealt 29-year-old catcher Jose Lobaton and 22-year-old prospects Felipe Rivero (LHP) and Drew Vettleson to the Nationals to get Karns.

Rivero was on the Rays' 40-Man Roster and joined the Nationals' after the deal, so he's in Spring Training. Williams said today he was impressed with what he's seen from Rivero so far.

The Nats' new skipper got a good look at the newest left-hander in the system when the 6'0'' southpaw threw his own live batting practice. Williams was watching closely.

"I just wanted to see what kind of depth -- again, we haven't really seen him much, I certainly haven't seen him much, and I just want to see the depth to his pitches," the first-year manager explained. Rivero threw some breaking balls that impressed Williams, who was watching the pitcher's arm angle and trying to get a feel for what the now-former Rays' prospect is working with.

Washington's press release on the deal with Tampa Bay noted that Rivero's fastball "regularly sits at around 96 [mph]." Williams said this afternoon that he liked the curve too and was looking forward to seeing Rivero compete in live action. "It's good," he said of Rivero's breaking ball. "It's hard to tell until you really get into a game situation and see guys timing a fastball and him throwing an offspeed pitch," Williams explained, "so right now [hitters] have an indication of what's coming, so that's okay, but from what I saw it's got good depth and the down angle is good."

Yet another left-hander, 27-year-old starter Ross Detwiler, also caught Williams' eye on Sunday. The Nats' 6'5'' '07 1st Round pick told reporters, including the Washington Post's Adam Kilgore, that he was working on adding a cutter to his repertoire. Williams explained why he thought it was a good idea for the 27-year-old candidate for the fifth spot in the Nationals' rotation.

"It just opens up both sides of the plate for him," the former major league slugger said. "Because his fastball runs naturally and when he really tries to make it run it runs hard. And he's relied on that pitch a lot, so the curveball for a strike, cutter in to the righties on the hands certainly opens up everything for him."

Adding a pitch which he can throw inside to right-handers makes it more difficult for hitters who, previously, could have cut out an entire side of the plate when facing Detwiler.

"I always look at it from a hitter's perspective," Williams explained. "So, as a hitter, I wanted to eliminate one side of the plate. So if I can eliminate him coming in to me, as a right-handed hitter, I'm going to have more success. But if he can throw that cutter in there, then he's equally effective on both sides and it just makes it more difficult for the hitter to square a ball up and feel comfortable."

"I mean, his sinker is a fastball and his cutter is a fastball," Williams continued, "but it's two completely different pitches for me. Again, I always look at it from a hitter's perspective, and what I would feel like standing up there and him being able to throw that cutter in here, especially for a strike. If he can do that, then it just opens up everything for him."

Nationals' Ross Detwiler On Nats' Rotation

Photo © Brad Barr/USA TODAY Sports

"They both start middle of the plate," Williams said of the similarity between sinker and cutter, "and then you have to commit. You feel like, as a hitter, you would feel like the ball is going to sink away. That's why the cutter is so effective for left-handed pitchers in general, especially for somebody like him who throws the ball so hard with very little time for somebody to react to it."

"It's a good pitch," he said. "It's a good pitch if he can control that ball in there."

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