Any hope that No. 13 Purdue has of winning the Big Ten regular-season title hinges on its visit to East Lansing, Mich.Following two consecutive losses, the third-place Boilermakers can’t afford to lose any more ground. They’re trying to catch Michigan and Michigan State, which hosts them on Tuesday night.Purdue dropped a 75-73 road decision to the Wolverines on Feb. 11, then fell at home to Wisconsin 94-84 on Saturday. Purdue dropped six spots Monday in the AP Top 25 poll, one place ahead of Michigan State at No. 14.As the latter score would suggest, Boilermakers coach Matt Painter is mainly concerned about shoring up his team’s defense for its showdown against the Spartans. Wisconsin shot 61.5 percent from the field and committed just three turnovers.”Their ability to break us down off the dribble and take us, I thought was really hard for us,” Painter said. “We had to do a better job guarding the basketball, and we just didn’t. And when you’re living in help (defense), now you’re really — if you don’t get them bottled up, that ball’s going to move quick. When you’re dealing with one of the best shooting teams in the country, they’re going to make you pay and they made us pay.”The Boilermakers (19-7, 11-4 Big Ten) wasted a 30-point performance from forward Trey Kaufman-Renn, who leads them in scoring (19.4 points per game) and rebounding (6.3). They had won 11 of their previous 12 games before the two-game slide.”You just move to the next game, whether you win or you lose,” Painter said. “Obviously, you want to take care of your home court and we didn’t do that (Saturday). We’ve had a couple losses at home now. You have to regroup, you’ve got to be better. A lot of times, what it gets to is just being better at what you do.”The Spartans will have to deal with Purdue’s veteran guard duo of Braden Smith (16.0 ppg, 8.8 apg) and Fletcher Loyer (13.9 ppg, 45.3 percent on 3-pointers).