(Julio Cortez/AP)

In his first season with the Nationals, Lidge knows, he will be counted on to toggle between roles, filling in when Drew Storen or Tyler Clippard need a night off. He also expects he may record more than three outs on occasion, something he has not done, incredibly, since September 2007. And he welcomes the chance.

“It’s something different, a different challenge,” Lidge said. “I’m kind of looking forward to physically challenging myself and feeling healthy and being able to do that. It’ll be a lot different from getting up and getting in, which I’ve done for a long time.”

The most-discussed aspect of Lidge’s signing with the Nationals has been the mentoring effect he could have on the Nationals’ young bullpen. But, really, his real contribution will come on the mound. If he can recapture the form he showed in his brief 2011 season, when he posted a 1.40 ERA in 19 1/3 innings after returning from a shoulder injury, Lidge will become an invaluable member of the Nationals bullpen.

Last year, Manager Jim Riggleman pushed Storen and Clippard to the brink, using them without relent when the Nationals had a late lead. Davey Johnson wants to protect both of them, and Lidge’s versatility – and willingness to shift roles – will allow Johnson to rest Storen and Clippard without jostling their routine. When Storen needs a break, Lidge can close, and when Clippard needs rest, Lidge can set up. When they’re both fine, he could pitch the sixth or seventh.

“I want to be able to help those guys in more than one way. On the field is the best way I can do it,” Lidge said. “I prepared myself for that physically. Mentally, it’s definitely an adjustment. I’m looking forward to that. I always still feel within me that I can close and close really well. But that being said, what this team calls for right now is for me to go out there and to be a set-up guy. I’m good with it.”

The key for Lidge is health. Last year, Lidge tore his rotator cuff during spring training and did not make his 2011 debut until late July. He wants to ramp up slowly during this spring, but, “I think I answered everything I needed to” last year, Lidge said. “It feels very healthy, very solid.”

When he returned last year, Lidge changed his approach on the mound. He was throwing his fastball – which once regularly zipped at 95 miles per hour – 88 or 89 mph. So he relied his slider, his best pitch almost exclusively – 72 percent of his pitches were sliders, according to data gathered by FanGraphs.com.

“That is extreme,” Lidge said. “I wouldn’t anticipate anything close to that this year. But 60 percent sliders is definitely a possibility. In a perfect world, I’d be 50-50. It could be more than that. It could be less than that if my fastball comes back then I thought and it’s working. At this point, we’re kind of getting a read on a hitter’s first swing or two during a game, and I go with what I see out there.”