Smith informed Pitino he was under the weather and was "going to give you everything that is humanly possible."
But Smith also said he told his coach that if he looked lethargic, "take me out."
The All-American sure didn't look sick in the second half, hitting 6 of 6 three-pointers and scoring 22 of his 26 points to help lead U of L to an 84-71 road win at SMU.
"He was just awesome," Pitino said. "What a performance. That is as good as it gets. That's a young man in college basketball taking over a game. A guy sick and that type of performance."
Smith, who also had five assists and two steals, said he threw up in a garbage can at least six times in the second half.
"Just looking at the garbage can made me want to puke more," Smith said.
It was a monster win for the Cardinals (25-5, 14-3), who snapped a 15-game winning streak at home by SMU. The Cardinals are now a half game ahead of Cincinnati in the AAC race.
U of L ends the regular-season with a home game at 2 o'clock on Saturday against UConn.
And it was also a nice rebound after a loss to Memphis on Saturday evening.
"I told them, guys I am upset at some of the things we did at Memphis and lost the game," Pitino said. "But those are part of the game. What I am more upset is the way we have won the past two or three years, we wear people with our offense, fast-break and pushing the pace.
"I told them we can't play slow. I told them I wanted to push the pace and Chris did."
Chris Jones was fantastic for the Cardinals with a career-high 21 points and six steals. He was playing after his step-brother was shot and killed in Memphis on Saturday.
And after a poor performance - 1-for-10 against the Tigers. He hit four three-pointers in the first half to help U of L rally from a 26-12 deficit early in the game.
Montrezl Harrell added 19 points, while Stephan Van Treese didn't score but he had five rebounds and made a ton of hustle plays.
"(Van Treese) gave us a tremendous lift," Pitino said. "He missed a layup and I told him, 'Don't get down on that you are a bad layup shooter.' He gave us great rebounding and kept the ball alive so many times. He was big."
And perhaps even bigger was the Cardinals overcoming a slow start and in a hostile environment. The Mustangs were undefeated at home all season and the game was billed as the "hottest ticket" in school history.
The fans were loud and crazy.
"These people must be on medication," Pitino said. "The things they yelled, the profanities. I was almost embarrassed for them.
"But we did a great job. We played smart basketball tonight."