Williams threw 25 pitches, including 14 strikes, did not walk a batter and recorded strikeouts of Mark Teixeira and Jeff Francoeur.
"This time of spring it's all about getting outs and feeling comfortable," said Williams, who was 8-15 with a 5.27 ERA last season. "First inning, I made a few good pitches but I wasn't too consistent. Second inning, I went out there and made the pitches I needed to make and was a lot better. [It's] definitely something to build on."
Williams faced the minimum in an Atlanta lineup that also included projected starters Kelly Johnson, Brian McCann and Mark Kotsay.
"For the most part, I was able to throw the fastball and didn't make mistakes over the plate," Williams said. "If I missed, I missed off the plate. [Their] hitters are so good, they'll tell you when you're going well and when you're not. It was a good lineup and obviously the pitchers are ahead of the hitters right now, but if I'm throwing like this in a couple of weeks I'll be OK."
The Astros are counting on the 41-year-old to take a firm grip on a rotation spot. He'd love to oblige.
"I knew I had a bad season," Williams said. "[Astros owner] Drayton [McLane] told me to forget about last year and focus on this year, and that's what I'm trying to do."
Tall order for Roy O: Manager Cecil Cooper was only half kidding when he said Roy Oswalt's "got to go 30-6 or something" for the Astros to win this year.
"With our 'pen the way I envision it and Roy pitching deep into games a lot, there's no reason why he can't get pretty close to something like that," Cooper said.
Oswalt, 30, won 20 games in both 2004 and 2005. He went 15-8 with a league-leading 2.98 ERA two years ago, and 14-7 with a 3.18 ERA last year as poor run support cut into his win total. Oswalt has allowed three or fewer runs in 33 of his last 42 starts.
"He should break out and have a phenomenal season," Cooper said. "We're going to go as far as he takes us. Other guys have got to chip in, but he's got to be the monster. I always tell him he's the best on the planet."
Berkman back Sunday: Lance Berkman has been held out of games, as the Astros wanted to give his sore quad muscle more time to heal, but the first baseman will be back in the lineup on Sunday against the Nationals.
"[We'll] turn him loose tomorrow right-handed," Cooper said. "They've got back-to-back lefties going to pitch for them, [so I'm] going to give him a chance to hit right-handed a little bit. One more day not having to hit left-handed, then we'll start him up on Monday from the left side."
Berkman isn't behind, since his only restriction was on hitting from the left side.
"He's been doing all his defensive work and everything, it's just been tough to hit left-handed," Cooper said. "He's past all that."
Eye on a dozen: Cooper said it was looking "probably 70-30" towards taking 12 pitchers when the club breaks camp.
"Right now anyway," he said. "It really kind of depends on the makeup of the 'pen. We've got three or four, five guys who can pitch multiple innings and do a lot of stuff. We need to kind of come up with guys who can bridge the gap between those middle long guys and [closer Jose] Valverde. Right now, it's [Doug] Brocail."
Oscar Villarreal, Geoff Geary and Dave Borkowski are among the relievers in that mix. How it plays out will also depend on whether one or more of the youngsters -- like Felipe Paulino -- earn a spot.
"We don't have a lot of guys who strike out a lot of people, so we're going to have to throw strikes and let our defense work a little bit," Cooper said. "You can't stop the other team when they're always getting free passes. I'm looking for guys who throw strikes and aren't afraid to pitch to contact."
Quotable: "He's a guy with a lot of talent and a lot of tools -- same goes for Reggie Abercrombie. We just need to see some consistency in swinging the bat." -- Cooper, on outfielder Yordany Ramirez
Extra bases: Kaz Matsui was back in the lineup Saturday, one day after being scratched from the batting order after what was originally announced as hemorrhoids before Cooper later said that wasn't the case. "He's good to go," Cooper said before the game. "We're not going to go into the details. He's fine, said he could go. I'm kind of anxious to see him in there." ... Cooper inserted Carlos Lee in the designated hitter spot Sunday to take a look at Abercrombie in left field. "You know how [Lee] loves to play defense," Cooper said, chuckling. "I'll keep him around and let him chirp a little bit in the dugout, and [Sunday] he'll have to go nine innings. You can tell him I said that. He'll come charging in here and I'll have time to defend myself." ... Darin Erstad will serve as designated hitter on occasion, but Cooper won't start playing the veteran more in the field until around the middle of the month. "I know what he can do," Cooper explained. "Guys like him and [Mark] Loretta and [Geoff] Blum, they're going to hit."
On deck: Shawn Chacon, bidding for a spot in the Houston rotation, gets a chance to make his case Sunday when he starts against the Washington Nationals in a 1:05 p.m. ET game at Osceola County Stadium. Paulino, Wesley Wright, Valverde, Mosh Muecke and Mike DeJean are also scheduled to pitch for the Astros. Left-hander John Lannan is scheduled to start for the Nationals.
The Astros will send a split squad up Highway 192 to face Atlanta on Sunday at 1:05 p.m. at Disney's Wide World of Sports. Brandon Backe will make his first start of the spring against Atlanta left-hander Mike Hampton. Chris Sampson, Geoff Geary and Chad Paronto will also make the trip.