Just another playoff game for Roy Halladay

The Phillies have four aces, but the team’s true No. 1 goes by 34.

Roy Halladay will take the mound in a do-or-die Game 5 Friday in the NLDS against the wild-card St. Louis Cardinals.

“Roy Halladay is the best pitcher in baseball,” Yankees GM Brian Cashman said during spring training. “I think if you asked most people in baseball who they would want on the mound for a big game, it would be him.”

Well, ‘Doc’ gets the call in the biggest game of the season — and possibly his career. For the Phillies, the pros are obvious.

After a shaky start against the Cardinals in Game 1, in which he gave up a three-run homer to Lance Berkman, Halladay didn’t yield anything. The uber-focused hurler set down the last 21 batters he faced leading the Phillies to a victory. The only other pitcher to accomplish that feat in the playoffs is the Yankees’ Don Larson, who pitched a perfect game in the 1956 World Series.

“The things that he [Halladay] does are amazing,” Shane Victorino said. “He’s just on another level.”

No pitcher has been better than Halladay in a division series, either. He has given up hits in just two of 17 innings in his NLDS career — and has been perfect in 14 of those 17 innings.

“The reason he can do that is because he’s Roy Halladay,” Phils reliever Michael Stutes said.

So it would be hard to imagine that Halladay, who pitches as if ice water runs through his veins, would feel any pressure.

“It’s another postseason game, really,” Halladay said Thursday. “I don’t think you can get too caught up in what game it is and what it means.”