Indianapolis — Michigan State coach Tom Izzo thinks Butler looks a lot like those stingy, grind-it-out teams he sees all season in the Big Ten. He means it as a compliment.

Butler has ridden a 25-game win streak into the NCAA championship game against Duke on the strength of its rugged defense. It came up big again Saturday night, holding Michigan State to 43 percent shooting in a 52-50 national semifinal victory.

It wasn’t always this way.

Butler had a lackluster 5-4 stretch early in the season. The Bulldogs were particularly unhappy with a 67-57 loss to UAB on Dec. 22 and had a team meeting to discuss it.

They haven’t lost since, giving up an average of 57 points per game and never more than 69 in the streak. NCAA tournament opponents haven’t scored more than 59.

“We were losing because of our defense,” forward Avery Jukes said. “It wasn’t where it should have been, it wasn’t where it was last year. Basically, ever since then, we’ve emphasized defense first.”

Coach Brad Stevens said “playing undersized” means he needs versatile players to guard multiple positions. And he remembers his team finally turning a corner on defense after the early struggles.

“I thought our guys made a commitment,” Stevens said. “We wrote it down on their lockers — need two more stops a game to go from a 46 percent field goal percentage defense to 40 percent field goal percentage defense. When you look at it that way, it sounds doable.”

The streak includes nine games in which Butler trailed at halftime, but clamped down in the second half and wound up with a victory:

n Butler 72, Green Bay 49: Bulldogs hold Green Bay to 35 percent shooting and force 15 turnovers. Butler wins second half 37-22. Shelvin Mack scores 14.

n Butler 80, Milwaukee 67: Bulldogs outscore Milwaukee 23-11 at free-throw line. Mack scores career-high 25.

n Butler 77, Wright St. 65: Butler outrebounds Wright St. 31-18. Gordon Hayward has 20 points and nine rebounds. Wright St. shoots 41 percent.

n Butler 64, Detroit 62, OT: Hayward has 17 points and seven rebounds. Butler wins despite 6-for-21 3-point shooting. Only OT game during the streak.

n Butler 64, Cleveland St. 55: Down one at the half, Bulldogs win second half 34-24. Butler shoots 54 percent and makes 6 of 10 3-pointers. Defense forces 17 turnovers.

n Butler 91, Youngstown St. 61: Mack scores 24 points and Matt Howard adds 22. Butler shoots 57 percent.

n Butler 48, Loyola of Chicago 47: Mack and Hayward score 12 points each. Butler shoots just 36 percent, but Loyola is worse at 34 percent.

n Butler 84, Illinois-Chicago 55. Hayward has 25 points and eight rebounds; Mack has 15 points and six assists. Butler shoots 56 percent while UIC shoots 38 percent.

n Butler 75, Green Bay 57: Rahmon Fletcher scores 24 points for Green Bay, but his teammates shoot 11 for 33. Howard scores 18 points. Butler shoots 55 percent.

n Butler 73, Milwaukee 66: Milwaukee leads 35-34 at halftime. Bulldogs pulls away to win despite being outrebounded 40-33.

n Butler 63, Detroit 58: Bulldogs win despite committing 21 turnovers. They make up for it by outrebounding Detroit 35-25.

n Butler 74, Wright St. 62: Butler shoots 68 percent from the field and 89 percent from the line. Outrebounds Wright St. 25-16 and gets 19 points from Willie Veasley.

n Butler 62, Loyola of Chicago 47: Butler grinds this one out despite 36 percent shooting. Bulldogs outrebound Ramblers 38-29 and make 16 of 18 free throws.

n Butler 68, Youngstown St. 57: Butler overcomes 18 turnovers by shooting 56 percent and making 8 of 16 threes to win Horizon League title.

n Butler 70, Cleveland St. 59: Howard has 21 points and 13 rebounds; Hayward adds 19 points and 11 rebounds. Butler outscores Cleveland St. 25-12 at the free-throw line. Butler wins rebounding battle 46-20.

n Butler 73, Illinois-Chicago 55: Four players score in double figures. Bulldogs hold UIC to 31 percent shooting, including 8-for-29 shooting inside the 3-point line.

n Butler 70, Siena 53: Bulldogs demolish eventual NCAA tournament qualifier. Siena leads 31-28 at the half, but the Bulldogs roll 42-22 after the break.

n Butler 74, Valparaiso 69: Veasley scores 20, Howard 17 and Mack 16. Butler trails at the half and gives up the most points during the streak. Cory Johnson scores 28 for Valparaiso, but teammates shoot 14-for-42.

n Butler 68, Milwaukee 59: Five Butler players score in double figures in Horizon League semifinal. Butler again trails at halftime.

n Butler 70, Wright St. 45: Bulldogs shoot 52 percent to win Horizon League title game. Wright St. shoots 35 percent.

n Butler 77, Texas El-Paso 59: UTEP leads 33-27 at break before Bulldogs clamp down and outscore them 50-26 in the second half of NCAA tournament first-round game. Mack ties career high with 25 points.

n Butler 54, Murray St. 52: Butler overcomes 36 percent shooting and 39-22 rebounding disadvantage by forcing 18 turnovers. Ronald Nored finishes with 15 points and six assists.

n Butler 63, Syracuse 59: The Bulldogs upset the top-seeded Orangemen, opening a 35-25 lead at the break and holding on. Mack shoots just 5 for 19 and Howard 3 for 9, but Syracuse commits 18 turnovers.

n Butler 63, Kansas St. 56: Kansas State, coming off a 101-96 double-overtime win over Xavier, shoots just 39 percent against Butler. Bulldogs stun everyone but themselves by outrebounding the No. 2-seeded Wildcats 41-29 to overcome 20 turnovers.

n Butler 52, Michigan St. 50: Hayward has 19 points and nine rebounds to help the Bulldogs advance to the final. Butler shoots 15 for 49 but forces 16 turnovers and battles the Big Ten powerhouse to a near draw on the boards, losing only 36-32 (and winning 11-8 on offensive glass).

So what about Duke?

Nored said the Bulldogs watched film Sunday and “we didn’t talk about offense one bit. It’s all about defense.”

“The last thing we’ll look at is attacking teams,” he said. “I think our defense is going to be what carries us.”

Veasley said the Bulldogs believe they can win any game because of their defense.

“Our confidence has been there this whole streak, and I think with each game, it just grows and grows,” Veasley said. “We don’t really worry about the small school thing. We think we can play with any team in the country.”