Top-25 powers collide in Indianapolis as the #21 Auburn Tigers face the #6 Purdue Boilermakers. Bryan Bash breaks down the efficiency gap and why Purdue’s elite ball movement—led by Braden Smith—makes them a formidable 8.5-point favorite in this neutral-site showdown.
The Setup: Auburn at Purdue
Purdue’s laying 8.5 at Mackey Arena against Auburn, and at first glance, this feels like a respectful number for a top-15 matchup. But here’s the thing – when you dig into the collegebasketballdata.com efficiency numbers, this spread might actually be undervaluing what the Boilermakers bring to the table at home. We’re looking at the #11 team nationally in adjusted net efficiency (23.4) hosting a Tigers squad that checks in at #45 (14.6). That’s nearly a 9-point gap right there before we even factor in home court.
Auburn comes in at 7-3, but those three losses tell a story: 68-97 at Arizona, 72-102 at Michigan. When the Tigers step up in competition and play away from home, they’ve been getting boat-raced. Purdue’s 8-1 with their only loss coming to Iowa State, and they’ve been absolutely dominant at home, including an 85-57 demolition of Minnesota in their last outing at Mackey. Let me walk you through why this number makes sense and why I’m leaning toward the home side.
Game Info & Betting Lines
Matchup: Auburn (7-3) at Purdue (8-1)
Date: December 20, 2025
Time: 6:30 PM ET
Venue: Mackey Arena, West Lafayette, IN
Spread: Purdue -8.5
Total: 153.5-154
Season: 2025-26
Why This Number Makes Sense
The efficiency gap here is exactly what you want to see when backing a favorite. According to collegebasketballdata.com, Purdue ranks #7 nationally in adjusted offensive efficiency at 123.8, while Auburn sits at #19 (120.9). That’s a solid edge, but it’s the defensive side where this game gets interesting. The Boilermakers check in at #42 in adjusted defensive efficiency (100.4), while Auburn’s defense ranks #141 (106.2). That’s a 5.8-point swing in defensive efficiency alone.
Here’s why this line makes sense: Do that math over 68 possessions – the likely pace given Purdue plays at 66.7 (#248) and Auburn at 68.5 (#179) – and you’re looking at roughly a 10-11 point expected margin before home court. The 8.5 number is actually giving Auburn a slight discount, probably respecting their offensive firepower and Keyshawn Hall’s ability to take over games.
But I keep coming back to those defensive efficiency numbers because they’re just too extreme to ignore. Auburn’s allowing 76.7 points per game (#258 nationally), which is brutal for a team with tournament aspirations. They’ve shown zero ability to get stops against elite competition on the road. Meanwhile, Purdue’s holding opponents to 69.1 per game (#93) while playing the more deliberate pace they prefer.
Auburn’s Situation
The Tigers can absolutely score – 85.9 points per game (#55) with an offensive rating of 121.2 (#63). Keyshawn Hall is a legitimate star, dropping 20.8 per game (#20 nationally) with 8.2 boards (#68). Tahaad Pettiford adds another 15.7 (#236), giving them a legitimate two-headed backcourt attack. They rank #31 in offensive rebounding percentage (36.0%), which means they create second chances and extend possessions.
Here’s the problem: Auburn’s a 33.9% three-point shooting team (#172), and they’re walking into one of the toughest environments in college basketball to face a team that ranks #10 nationally at 40.2% from deep. The Tigers also rank #250 in assists per game at just 13.3, which tells you they’re relying heavily on individual creation rather than ball movement. That’s not just a stat – it’s why Auburn struggles when their shot creators get bottled up by elite defenses.
And about those road performances: Getting blown out by 29 at Arizona and 30 at Michigan isn’t just losing – it’s getting completely overwhelmed when the environment gets hostile and the competition stiffens. Auburn’s defensive rating of 107.7 (#214) is concerning enough at home; on the road against top competition, it’s been a disaster.
Purdue’s Situation
The Boilermakers are humming right now, and it starts with Braden Smith, who ranks #2 nationally in assists at 8.7 per game while also contributing 13.1 points. That’s the engine that makes everything work. Purdue ranks #8 nationally in assists (20.2), which creates the open looks that fuel their #10 three-point shooting percentage. This isn’t hero ball – it’s systematic offensive execution.
Trey Kaufman-Renn gives them a double-double threat at 13.9 points and 10.7 rebounds (#11 nationally), while Fletcher Loyer provides perimeter shooting at 14.4 per game. Oscar Cluff adds 11.1 and 8.9 boards (#49), giving Purdue legitimate size and depth in the frontcourt. They shoot 49.9% from the field (#39) and 57.7% effective field goal percentage (#33) – those numbers scream efficiency.
The home court advantage at Mackey Arena is real. That 85-57 beatdown of Minnesota wasn’t a fluke – it’s what Purdue does to teams that can’t match their execution and shooting. They’ve scored 109, 81, and 85 in three of their last four home games. The pace might be slower (#248 nationally at 66.7), but that actually works in their favor against Auburn’s more frenetic style. Purdue controls tempo, forces you to execute in the halfcourt, and makes you defend for 30 seconds every possession.
The Matchup: Where This Gets Decided
This game lives and dies on the three-point line and halfcourt execution. Purdue’s 40.2% from deep (#10) against Auburn’s 32.0% three-point defense (#149) is a massive advantage. Meanwhile, Auburn’s 33.9% shooting from three (#172) against Purdue’s 32.0% three-point defense (#149) is basically a wash. The Boilermakers have a clear edge in the most important area of modern basketball.
The assist differential tells the story of this matchup: Purdue’s 20.2 per game (#8) versus Auburn’s 13.3 (#250). That’s seven extra assists per game, which translates to better shots, better spacing, and better offensive execution. In a slower-paced game where possessions are precious, that efficiency gap becomes enormous. Do that math over 68 possessions, and you’re looking at Purdue getting significantly better looks throughout the game.
Here’s the matchup that seals it for me: Auburn’s #258 ranking in opponent points per game (76.7) against Purdue’s systematic, patient offense that ranks #7 in adjusted efficiency. The Tigers haven’t shown they can get consecutive stops against elite offenses, and Purdue’s going to get great looks all night with Smith orchestrating and multiple shooters spacing the floor.
Auburn’s one path to covering is if Keyshawn Hall goes nuclear and they dominate the offensive glass (#31 in offensive rebounding percentage at 36.0% versus Purdue’s #92 at 33.9%). But even if they create extra possessions, they still have to convert them against a top-50 adjusted defense in a hostile road environment.
My Play
The Pick: Purdue -8.5 (2 units)
I’ve considered Auburn’s offensive firepower and Hall’s ability to take over games, but the defensive deficiency is still too massive to ignore. When Auburn’s faced elite competition on the road this season, they’ve been blown out by an average of nearly 30 points. Purdue’s not quite Arizona or Michigan, but they’re close enough – and they’re at home where they’ve been dominant.
The efficiency gap, the three-point shooting advantage, the assist differential, and the home court environment all point to Purdue controlling this game from the opening tip. Auburn’s going to score some points – they’re too talented not to – but I don’t see them getting the stops necessary to keep this within single digits.
The main risk here is if Auburn gets hot from three and Purdue goes cold, but the shooting percentages suggest that’s unlikely. I’m projecting something in the neighborhood of Purdue 82, Auburn 71, which gives us plenty of cushion on the 8.5.
This number feels like it’s respecting Auburn’s talent without fully accounting for their defensive struggles and road woes. Lay the points with the Boilermakers at Mackey.
