If the Saints can win two more games in a row, they'll finish the season at the Class 4A state tournament in Des Moines.
The sixth-ranked Saints held Linn-Mar to 16 points in the first three quarters Friday night and hung on for a 40-35 victory in the final game of the regular season at Ron Thillen Gymnasium.
Xavier will take a 15-6 record into the regional semifinals next Saturday night at home and would host the regional finals on Tuesday, Feb. 21 if they are still alive.
"I like where we're at, except maybe free throws," said Xavier Coach Tom Lilly after the Saints swept the season series from Linn-Mar for the first time in five years.
The Saints finished only 11 for 21 at the free throw line, helping the Lions chop a 14-point deficit to only four points in the final stages before time ran out on the visitors.
Linn-Mar got back into the game with a trapping zone defense that forced turnovers and left the Saints standing around too much, waiting for something good to happen instead of being aggressive.
"We were holding on for dear life," said Lilly.