Fister to throw Tuesday (with Ohlendorf, Mattheus, M. Gonzalez updates)

VIERA, Fla. - Manager Matt Williams said this afternoon that right-hander Doug Fister, who has been sidelined since his first spring training appearance last Sunday with inflammation in his right elbow, is progressing and will throw off flat ground tomorrow. The Nationals have been taking a cautious approach with Fister, treating the elbow issue with anti-inflammatories and ice, and Williams said that enough of the inflammation has cleared that Fister can get back to playing catch tomorrow. "He's doing good," Williams said. "Feeling good. We'll start his throwing program." Fister first felt discomfort in his elbow after his March 2 spring debut against the Marlins, an outing in which he allowed one run on two hits with a walk and two strikeouts over two innings. After an MRI showed the inflammation in the elbow, the Nats scratched Fister from his next scheduled start and have been treating him since then. Just because Fister is back to playing catch doesn't mean that he's out of the woods yet. The Nats will continue to take things slowly and make sure that the righty doesn't feel any more discomfort after throwing tomorrow before planning out a further timetable. "We gotta make sure that he's good to go with every step, and that's the first one," Williams said. Right-hander Ross Ohlendorf is also progressing from an injury - lower back spasms - which he felt during his spring debut Thursday against the Braves. "Threw today. Played catch today," Williams said. "Will do it again tomorrow if all goes well. Was good today, though. He's on his way back, which is good." Ohlendorf has been set back by a number of different ailments this spring - first tightness in his side, then one of the fingers on his throwing hand splitting open, and now the lower back spasms. He only faced four batters in his debut and didn't retire any of them, so he still has a little ways to go as he tries to build up arm strength before the regular season. Meanwhile, right-handed reliever Ryan Mattheus has thrown from up to 90 feet, Williams said, and is also progressing as he works back from inflammation in his chest. Mattheus has yet to appear in a spring training game after feeling pain in his chest following his second bullpen session of camp. He's been shut down since then, and was cleared to start throwing again last week. "He came out of his throwing program yesterday good and so we'll continue to progress him now," Williams said. "Stretch him out. But things are good. He felt good after yesterday." Finally, left-handed reliever Michael Gonzalez, signed to a minor league deal last week, threw a bullpen session in front of Williams, pitching coach Steve McCatty and others yesterday, and Williams said that the veteran southpaw looked sharp. Gonzalez will appear in a game on the minor league side tomorrow, and if all goes well, he'll then cycle into the Nats' throwing schedule and start appearing in Grapefruit League games. "He told us that he had been throwing and it was evident in the bullpen. He looked really good," Williams said. "I think he's prepared. We'll see how he comes out it and he feels after it. Again, not seeing him throw, guys say they've been throwing but yesterday it was evidence that he had been. He was sharp in his bullpen and velocity was there. He'll cycle right in as quickly as we can get him in so we can take a look, too."