McCartney, the grandson of former Buffaloes coach Bill McCartney, picked up a Michigan fumble and returned it 18 yards for a first-quarter touchdown that gave underdog Colorado a two-score lead.
Earlier this week, McCartney told ESPN.com that this would be a special game because his grandfather and several other family members were making the trip to Michigan, where Bill started his career as a college coach.
"I think the thing that’s going to be special is that my grandpa is going to be there and my family is going to be there with me," he said.
Bill McCartney, a Michigan native, coached with Bo Schembechler's Wolverines staff for eight seasons before moving on to win a national championship at Colorado. He was also the head coach when Colorado upset No. 4 Michigan in September 1994 on a last-second Hail Mary pass known as the "Miracle at Michigan."
The older McCartney said this is his first trip back to Michigan Stadium since that day. McCartney was diagnosed with late-onset Alzheimer's disease this summer and said he was looking forward to seeing Derek play at his old stomping grounds this week.
"The only reason I’m going back to this game is it’s Colorado and I’ve got blood in the game," McCartney told ESPN.com earlier this week. "It's going to be a special day."
Derek capitalized on an early chance to make it even more special than the McCartneys could have thought.