PHILADELPHIA —- Roy Halladay and Tim Lincecum have little in common except performance on the mound.

Nicknamed the Freak, Lincecum is a shaggy-haired, skinny kid who looks more like a bat boy than one of the best pitchers in the majors.

Known as Doc, the bearded Halladay is bigger, stronger and can probably pass for a professor.

Lincecum is quirky. He has an unorthodox delivery, doesn't ice his arm, and munches on treats like Philly cheesesteaks or ice cream before starts.

Halladay is robotic. He has perfect mechanics, a tireless work ethic and doesn't let anything prevent him from following his routine.

Who's the better pitcher?

They'll showcase their stuff when the San Francisco Giants play the two-time NL champion Philadelphia Phillies in Game 1 of the league championship series tonight at Citizens Bank Park.

"It's going to be a tremendous matchup," Giants manager Bruce Bochy said Friday. "You have two of the best pitchers in the game. We have all the respect for Halladay. Tremendous command in the strike zone, great stuff, great competitor. And, we have a good one going, too. Two different styles. Their guy's probably a little bit more conventional than Tim with his unique delivery. But when it comes down to it, he's in the same position. They have four-plus pitches they can throw at any time with good command."

Both pitchers were sensational in their postseason debuts last week.

Halladay threw the second no-hitter in postseason history in Philadelphia's 4-0 victory over Cincinnati. A day later, Lincecum tossed a two-hitter with 14 strikeouts in San Francisco's 1-0 win over Atlanta.

Neither guy expects an encore. It doesn't mean they're not trying.

"That's the beauty of it. I don't look at it as pressure. I look at it as a challenge," Halladay said. "Getting to this point, you put in so much work to get here that once you do, it's been nothing but excitement. And you don't feel like there's a certain standard you have to live up to. I feel like I need to go out and pitch the way that I normally pitch, execute pitches and be aggressive. It's been nothing but a challenge and something I look forward to. I just haven't felt the pressure of having to live up to something or do something."

Lincecum certainly won't be overwhelmed by the spotlight.

"You get a taste of what it's like to play in postseason ball. I think it can't do anything but help me," he said about his success in his first start. "I feel like the All-Star game last year helped me prepare for the postseason scenario, just with the heightened atmosphere and how crazy it gets. But my approach on this game is the same as any other start Obviously, it's a big game. But I don't want to get too overamped. I want to take it just like any other start."

Halladay lived up to enormous expectations in his first season in Philadelphia after 12 years with Toronto. The 33-year-old right-hander finished 21-10 with a 2.44 ERA. He tied CC Sabathia for most wins and led the majors in complete games (nine), shutouts (four) and innings (250 2-3).

Halladay threw a perfect game in May, made his seventh All-Star game and is the leading candidate to win his second Cy Young Award.

While Lincecum is freakish in that he doesn't follow standard practices, Halladay goes overboard. He's legendary for his workout routine that starts at 5:30 a.m.

"There's never a guarantee of whether a guy's going to be good or not, or how good he can be," Halladay said. "It just kind of happens. I think there's a lot of internal makeup that's involved. But it's a great part about this game. You don't have to be 6-9 and 280 pounds to be a defensive lineman. You can take all different shapes and sizes and do the job. So that's what makes it fun."

Cole Hamels, the 2008 World Series MVP, said he tried working out with Halladay once in spring training. He didn't make it back for another day.

"It's insanity. I have a newborn. I needed every minute of sleep I can get it," Hamels said. "He gets there at 5:30. That means he's up at 4:30. That's the personality he has and he's had success with it."

Even after throwing a no-hitter, Halladay didn't take a break from his normal day. He turned down an invitation to David Letterman's "Late Show" and other media appearances.

"As far as who he is and how he goes about things and what makes him good, those are the things that I feel like I've learned about him," Phillies manager Charlie Manuel said. "And the things that I think are better than what I really imagined was definitely his command and his routine. It's so regimented, He's so focused and everything."

Lincecum, the reigning two-time Cy Young Award winner, had an up-and-down year after emerging as the most dominant pitcher in the league in his first two full seasons. The 26-year-old righty rebounded in September after a career-worst five-start losing streak in August, and finished 16-10 with a 3.43 ERA.

The Halladay-Lincecum matchup is the marquee pitching duel in a series that features a handful of aces. San Francisco flip-flopped its Nos. 2 and 3 starters, and will send Jonathan Sanchez against three-time All-Star Roy Oswalt in Game 2. Matt Cain faces Hamels when the series shifts to AT&T Park on Tuesday.