Facing perhaps the most important but challenging game of the season, USF coach Stan Heath has some confidence he can turn to.

USF’s chance at staying in the NCAA tournament at-large hunt may ride on upsetting No. 8 Villanova on the road tonight at 9 in the Pavilion, one of two home venues the Wildcats use and where they’ve won 36 straight dating back to 2007.

But the Bulls went through this before, Heath said, when they beat then-No. 8 Georgetown on its home court Feb. 3 right after the Hoyas blew out then-No. 6 Duke 83-64.

“The Georgetown win helps us when we go on the road,” Heath said. “It gives us a sense (that) we’re going in a hostile environment, we’re playing against a really good team – Georgetown’s case, a ranked team – and we found a way to get the job done.”

USF (16-10, 6-8), which is chasing its best record since it went 19-13 in 2001-02, is no stranger to upsets this year – also defeating then-No. 17 Pittsburgh on Jan. 31.

Heath, however, said the Bulls, whose NCAA tournament hopes are slim right now, have to play one of their best games of the year to beat Villanova, a team that’s been ranked in the top 10 the entire season. USF is coming of a crushing blow – a home loss to St. John’s.

“We’ve had some slow starts in games,” Heath said of recent Big East losses. “The Notre Dame game we were down 16-2. (For) Marquette, I thought we let things get away at the end of the first half. I thought the same thing happened last game. We can’t have those bad four or five minute segments, especially on the road and especially against a team like Villanova.”

Nor can the Bulls afford to play defense like they did Saturday, when St. John’s had a number of transition layups and shot 59 percent from the field. Senior guard Mike Mercer said USF will be ready to play tonight.

“Like Coach Heath always says: the Big East is the Big East and you really can’t get too down on one loss,” said Mercer, who had 17 points Saturday. “It’s in the past. There’s nothing you can do about it. We’ve got Villanova (tonight) and, personally, I’m going to make a conscious effort to have my best defensive game.”

Villanova (22-4, 11-3), which is coming off consecutive losses to Connecticut and Pittsburgh, doesn’t have a starter taller than 6-foot-8, and its second tallest starter is 6-foot-5. Even though USF has a height advantage, looks can be deceiving, Heath said.

“You’re going to see a lot of things (with Villanova’s defense) that a lot of teams aren’t usually playing,” Heath said. “The forward positions – the three, four and five – are so interchangeable and so movable that they can do things that are a little bit unconventional. The key is having some ball movement and player movement before you attack … It’s a difficult team in a lot of ways.”

Wildcats senior guard Scottie Reynolds, a front runner for Big East Player of the Year, averages 19 points per game and shoots 41 percent from 3-point range. USF junior guard Dominique Jones is the league’s second leading scorer with 21.6 points per game, however.

USF, which is 2-5 on the road this year, has never beaten Villanova.

“Villanova is coming off two losses, so they’re not going to be a very happy bunch of guys,” Heath said. “We just laid an egg so we’re not very happy either.”