Jourdan Lewis received the squib kick at his own 11, advanced and danced at the 25 and made a break away down the Michigan sideline. Austin Mack was the end man to the field side of the kickoff and most likely was in charge of holding outside leverage and keeping contain.
He got sucked all the way in between the numbers and has on the short side of the field when Lewis made a break for it. Mack fought off a block to seal the edge and force Lewis to cut inside at the 45 and probably saved a touchdown. I think if Lewis just kept going to the sideline he might have even had a shot at getting outside and around Mack for the TD.
This play was scary on Saturday but even more so looking at the replay.