Hardwick said the Tigers faced a tough selection decision with ruckman Ivan Maric, however, after he played through an ankle injury against Port Adelaide in round seven.
Cotchin (knee) and Vickery (concussion) have both been declared fit and Hardwick said the Tigers weren't in a position to rest available players against opponents they were expected to beat.
"He (Cotchin) had his rest last week and he's well and truly ready to go this week," Hardwick said on Thursday.
"If we had our time again he probably wouldn't have played (against Geelong in round six).
"But the reality is he's a tough kid and last week we made the decision that he couldn't put himself through that again."
On Maric, who injured an ankle against Geelong and played under duress against the Power, Hardwick said the Tigers would consider their ruck options.
Mature-age rookie Orren Stephenson came into the team against the Power and played well, and with Vickery back in the mix Hardwick said three wouldn't go into two.
"It was enormous last week for him to play, considering we were down two rucks," the coach said of Maric.
"We were really pleased that he got up and played. Did he play to the best of his ability? Probably not."
With Ricky Petterd (calf) still another week away from being available, Hardwick said Aaron Edwards, Matt White, Matt Dea and Matthew Arnot would come into the selection mix to replace Chris Knights (knee) and Shane Tuck (shoulder).
He paid respect to the 1-6 Demons, and said his team would be up for a physical contest at the MCG on Sunday.
"They've been doing a lot of one-on-one, a lot of tackling work over at the Dees, so we've just got to make sure we bring our own heat and get our game up and going," Hardwick said.
"They're a better side than how they're playing, I've got no doubt that Mark Neeld would know that also.
"They're a side that has probably got a fair amount of criticism so we're under no illusions that we're going to be up for a hell of a contest."
Hardwick said Richmond had evolved into a team that expected to win every game it played, but the team wouldn't enter Sunday's match thinking, "lets win by 100 points."
"Any win that you can get a percentage boost like we did last week with a 42-point win is a great result," he said.