As well as Kevin Gillen has pitched for St. Joseph's Prep this season, coach Chris Rupertus didn't hesitate when it came to tabbing Kyle Mullen as the starter against West Chester East yesterday.

Late-week showers had forced two postponements and given Mullen, a standout postseason career performer, four days of rest after a complete-game win over Garnet Valley. And if the ace righthander happened to falter, Gillen's rubber arm was ready for relief action.

Mullen, who received an e-mail from Rupertus the day before notifying him about his semi-surprise start, didn't disappoint his coach. The 6-foot, 170-pound senior tossed a three-hitter and yielded no earned runs as the Prep held off East, 2-1, in a PIAA Class AAAA state quarterfinal at Everett Swanson Field on the Glen Mills campus.

"Four days, for me, is plenty of time to recover," Mullen said. "I was really excited when I got the e-mail. I wanted to come out here and pitch as well as I could."

Tomorrow, in a 2 p.m. semifinal at Spring-Ford High in Royersford, the Hawks (16-8) will take on District 11 champion Parkland (20-6). Gillen will get the start.

After allowing an unearned run in the bottom of the first, Mullen kept the Vikings (22-4) scoreless. In the fifth, when a pair of walks and a throwing error loaded the bases, he escaped by freezing Zach Mouton, East's No. 2 hitter, on a 2-2 pitch.

Mullen, who is headed to St. Joseph's, and Gillen, a righthander ticketed for John Hopkins, are close friends. When Rupertus turned to No. 3 instead of No. 9, there was only support.

"He's our best big-game pitcher," said Gillen, who played second base. "Obviously, if you want somebody on the mound when it really counts, you go to Kyle. He gives us a great chance to win."

Mullen entered with a 7-3 record, 1.82 ERA, and 83 strikeouts in 652/3 innings. Against East, ranked No. 2 in Southeastern Pennsylvania by The Inquirer, the 18-year old struck out seven and walked five. He threw 115 pitches, 65 for strikes.

"He was the best pitcher we saw all year, by far," Vikings coach Dean Owens said. "He lived on the corner, hit his spots when he needed to. If we were going to beat them, I wanted to beat their top kid."

The No. 7-ranked Hawks produced five hits, all singles, against hard-throwing righthander Neal Herring. Both of their third-inning runs were unearned. No. 9 batter Dan Turner (single to shortstop) scored on a fielder's-choice grounder, and leadoff man Gio Morales (walk) raced home on Jeff Lynch's sacrifice fly to center field.

Against Mullen, of Berwyn, East's top four spots in the order were a combined 2 for 12. Neither team was flawless in the field, with each committing three errors.

Mullen soon will become the fourth member of his immediate family to play baseball on Hawk Hill. His father, Mark, and two uncles, Tony and Kevin, were outfielders there.

St. Joe's Prep 002 000 0 - 2 5 3

W. Chester East 100 000 0 - 1 3 3

WP: Kyle Mullen. LP: Neal Herring.

Contact staff writer Rick O'Brien at 610-313-8019 or robrien@phillynews.com.