Williams currently leads the NFL with 394 yards, but Holmes isn't far behind at 386.
Whoever wins Sunday's battle might go a long way toward determining which team leaves Arrowhead Stadium with a victory.
All the Dolphins have great respect for Holmes, but maybe nobody more so than Williams, who was a sophomore during Holmes' senior year with the Texas Longhorns.
"I kind of looked up to him, and he taught me a lot about playing running back," Williams said this week. "He taught me a lot of mental toughness. He wasn't the biggest guy, but he would go after people like he was. He was a head-hunter. He would try to kill people."
The Dolphins are well aware that Holmes led the NFL in rushing last season after joining the Chiefs as an unrestricted free agent.
The year before, the Dolphins had brought Holmes in for a visit when he was a restricted free agent, but they wound up signing Lamar Smith as an unrestricted free agent to be their running back.
"He's got a great feel for making the right cuts," said Coach Dave Wannstedt. "He's a lot faster than people give him credit for. He makes a lot of long runs. The Patriots knew he was going to run the ball, and he still got 180 yards. That's a real compliment to him."
Holmes and Williams don't talk much these days, but they keep up with each other through mutual friends.
As friends and former teammates, they want to see each other do well. Except this week.
Said Williams: "I hope he doesn't run for too many yards."