Lyon told 6PR the young gun would take his place in the team against Port Adelaide at AAMI Stadium on Sunday.
Fyfe has been out of action since having a shoulder operation back in May.
Lyon said form forward Chris Mayne would also return to the side after missing the GWS game with a calf injury.
Defender Zac Dawson (knee) will be tested this week, as will Greg Broughton (back).
Lyon said Nick Lower, who sustained a concussion recently and missed Freo's past two games, came off the ground with nausea in the WAFL for Perth on Saturday.
But the senior coach said Freo was not yet sure if it was related to the concussion or because of illness.
Among others in selection contention were Lachie Neale, who had 35 touches for Swan Districts, in-form Peel defender Peter Faulks and Alex Silvagni.
Lyon said Freo was mindful that too many changes may not be a good thing.
"When u have a good win, you don't want to make yourself vulnerable with people being thin in terms of fitness and conditioning," he said.
"We've got to pick a team that can go over and get it done and we'll work through that at match committee."
