Mahomes suffered a high ankle sprain in the Chief's Divisional Round victory over the Jacksonville Jaguars but all week has been trending towards starting his fifth consecutive Championship game.
"He looks good," Reid told reporters. "I mean, he's moving around (well). He's going to go out and play."
After hobbling to a win last week, questions around the former MVP's mobility will persist but Reid believes his team can use scheme and coaching to mitigate any Mahomes limitations.
"We have enough in the game plan where you can kind of pick and choose where you want to go with it,'' he said.
"You have a variety of things that you can go to. Obviously you don't use all the plays in the game plan, but they're available and so if you have to go a certain direction, you can go that direction with the calls.''
Reid, the only NFL coach to win 100 games and appear in five consecutive conference championships with two different franchises, gave a brief health update but did not mention Sunday's opponents.
"Really, the only one that didn't practice was Justin Watson," Reid said. "He's sick. Everybody else went through this (and) did a nice job with it. Really, all week."
Chiefs defensive end Frank Clark also spoke to the media Friday, revealing that he believes Sunday's opponent Joe Burrow is the best pocket passer in the league.
"I feel like as a pocket quarterback, he's the best in the game," Clark said after being asked what makes Burrow tough to play against.
"He's got that Peyton Manning in him; no matter how many times he gets hit and knocked down, he's getting back up. He lifts his offense and if you're an immature defense, he'll pick you apart every time.
"In the last few games, he's been able to expose us in those aspects."
Following a regular season that saw him pick up 5+ sacks for the sixth time in his career, Clark earned his 12th postseason sack last week, tied fourth for the most since 1982.
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