McMillan ranks as a three-star prospect from one of the powerhouse programs in Texas high school football. McMillan tripped down to Baton Rouge this earlier this week for all three days of the Tigers' June camp.
Cam Cameron took note of McMillan's ability and extended him an offer. McMillan jumped on the opportunity, only previously having offers from schools like Arkansas State and UNLV.
"I was told they were going to offer me," McMillan said. "So I had to let them know I'm not looking [at any other schools], and they don't need to either."
McMillan spent most of his three days on campus alongside LSU offensive coordinator Cam Cameron, to whom he delivered the good news.
McMillan called Cameron an "offensive guru."
"We both were on the same page," McMillan said. "They knew when they offered they had me. I love everything about the school, from the academics to Mike the Tiger."
McMillan showed a strong arm during LSU's camp this past weekend. He measures 6-foot-2 and a lean 180 pounds.
"He has worked his tail off to get to this point," said his coach Joey McGuire, in an interview with Scout's Greg Powers. "He went to their three day camp and was on fire. They said he competed everyday in every drill. Strongest arm they had seen."
McMillan is the 12th member of the Tigers' 2015 class, the third from Texas and the first quarterback. He is also a high school teammate of five-star WR Damarkus Lodge, who is also a major LSU target.
McMillan completed 60 percent of his passes as a junior, racking up 2,500 yards of offense with 32 touchdowns. He helped lead his team to a state championship this past fall with a 14-2 record, and the Cedar Hill Longhorns are an early contender to be the nation's best team.
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