St. John?s Prep and Central Catholic will have the entire play-off stage to themselves Saturday.With the overwhelming majority of teams playing tonight, the Eagles will have the eyes of the region watching them at Cronin Stadium (2) when they face off against the Raiders.There will be tremendous interest in this game. For one thing, St. John?s has been better than advertised coming into the season. The Eagles are 7-1, with the only loss coming against Everett.For another thing, The Prep defeated Central, 27-12, earlier in the season in a game that was tougher than the final score would indicate. For just about the entire season ? save for last week?s 28-0 win over Chelmsford in which all the points came in the first two quarters ? the Eagles have been a second-half team. And that was certainly true in the Central game, as The Prep pulled away in the second half.Central coach Chuck Adamopoulos is certainly happy to have another crack at the Eagles. But he observed last Saturday, while scouting the Prep-Chelmsford game, that The Prep?s offensive and defensive lines look stronger now than they did in September.As for first-year coach Brian St. Pierre, he was thrilled with the way his defense played.?I had a feeling,” he said, “that we?d have a big week. I had a feeling that our defense was primed.”The Raiders struggled last Friday night against Andover, but shook off the Golden Warriors in the end, 28-21. After allowing Andover two first-period scores, the Raiders clamped down on defense and ended up with the win.As for St. John?s against Chelmsford last week, the star of the show was running back Cody Harwood, who finished up with 195 yards and scored three touchdowns. St. Pierre wasn?t at all interested on passing the ball on a wet, windy day and kept it on the ground.uIn a non-playoff game Saturday, Lynn Tech will play at 2 p.m. against Jeremiah Burke High School at Madison Park.