Donald Trump continues to defy expectations, and Monday was no exception as the Republican front-runner snagged an unexpected endorsement from former University of Notre Dame football head coach Lou Holtz. The legendary gridiron figure's support follows that of another illustrious Hoosier State sports figure: former University of Indiana basketball head coach Bobby Knight.

While Knight has clearly expressed his disdain for American politics — "Quite frankly, I could give a damn about the Republicans," he said last week during a Trump rally in offering his endorsement. "And on the other hand I don't give a damn about the Democrats, either" — Holtz has a history of chiming in on conservative causes. So in that respect, Monday's unexpected endorsement from Holtz shouldn't be a surprise at all. But his reasoning may have left some scratching their heads.  

"I wholeheartedly endorse Donald Trump as the next president of the United States," he started off in earnest before justifying his decision. "The main reason I'm endorsing him ... I've played his golf course, I've stayed in his hotel."

Holtz has made no secret about being a Republican and has rarely shied away from voicing his political opinion, as when he suggested in 2010 that then-House Speaker Nancy Pelosi, D-Calif., be fired. But two years earlier, Holtz donated to Hillary Clinton's first presidential run, the Daily Beast reported. Fast-forward to early 2013, and Holtz was lamenting about President Barack Obama's re-election: "I’m done, finished, the country’s [sic] over with — we’re not doing this again!"

Trump expressed his gratitude Monday morning for Knight's support, but the candidate experienced some missteps when doing so. First, his verified Twitter account tweeted how the "support of Bobby Night has been so amazing" before someone realized the spelling error, deleting the tweet and replacing it with another. A screengrab captures the error.

trump knight tweet Donald Trump's Twitter account misspelled Bobby Knight's last name in a tweet Monday. Photo: Screengrab

Hours later, during a rally in Carmel, Indiana, Trump reportedly called Knight "Coach K," according to a Huffington Post editor's now-deleted tweet. Coach K is, of course, a nickname that has been exclusively reserved for Duke University basketball coach Mike Krzyzewski. Other Twitter users corrected the editor, Igor Bobic, insisting Trump was referring to "Coach Keady," as in Gene Keady, Purdue University's former basketball coach. 

Purdue is in West Lafayette, Indiana.

Trump enters Tuesday's Indiana presidential primary heavily favored despite an attempt by rival candidates Texas Sen. Ted Cruz and Ohio Gov. John Kasich to collaboratively plot to prevent the front-runner from winning the state.

There are 57 delegates up for grabs in the Republican race, and Trump is looking to add as many of them to his already impressive 956. Cruz is the next-closest candidate with 546 delegates. Holtz and Trump may just be what he needs to get him closer to the Republican Party's presidential nomination. If not, the billionarire businessman could face a contested convention in June in Cleveland.