When Ethan Finlay was being challenged by Nashville ‘s Daniel Lovitz (2) on Tuesday, it was Finlay’s first action since Sept. 2 because of knee surgery. (The Minnesota Star Tribune)

In a condensed season when they changed the game's rules because of the coronavirus pandemic, Minnesota United coach Adrian Heath made a single substitution each in scoreless draws with Real Salt Lake and Nashville SC.

The International Football Association board that sets the rules approved for this season a FIFA request that allows two more substitutions — now up to five — per game because of a schedule often condensed into a blur after a four-month shutdown.

Heath has praised his team's improved depth in a season when he has shuffled his starting lineup almost nightly because of injuries, circumstance and the schedule's demand.

He made four starting 11 changes for Tuesday's game at Nashville from Saturday's 2-0 home victory over FC Cincinnati in a very rare — and short — three-day turnaround. Those changes compensated for the departure of starting central midfielder Jan Gregus to his Slovakia national team and starting left back Chase Gasper's yellow-cards suspension, and they allowed Heath to give 36-year-old striker Kei Kamara and workhorse Robin Lod some rest.

But once he picked his 11, Heath made only one change in each scoreless tie: Marlon Hairston for Jacori Hayes in the 77th minute against Real Salt Lake at Allianz Field on Sept. 27 and Kamara for Aaron Schoenfeld in Tuesday's 71st minute.

Real Salt Lake made five subs in that game and Nashville made three on Tuesday in games that ended with the same result.

"There's a fascination with substitutions in America," Heath said. "I don't understand it at times."

On Tuesday, Heath started veteran midfielder Ethan Finlay at Lod's position on the right side and played him all 90 minutes in Finlay's first game action since Sept. 2 because of knee surgery.

"I felt great," Finlay said on a video conference call with reporters afterward. "Until I had a little bit of a cramp in the leg in the calf, I was happy physically how I was able to hold up and play the whole game."

Heath stayed with his starters almost exclusively in both scoreless ties because he thought they were giving a better performance than the one-point result they earned.

Schoenfeld started his second game this season — his first since another scoreless tie with Real Salt Lake, in group play at the MLS is Back tournament — and played those 71 minutes before Kamara came on.

"I didn't want to change the rhythm of the team, and Ethan felt great," Heath said. "And Aaron has not played for a long while. We managed to get a good 70 out of him. And the rest of the guys felt good."

Heath was pleased with his team's second-half play in both scoreless ties these past two weeks. He was pleased enough that he saw little need to send new players and fresh legs into the games, which were the first and last in a three-game streak of clean sheets.

"When you're creating the chances that we are in the second half and are completely dominant, why would we upset the rhythm in the team?" Heath said after the Real Salt Lake game. "I could understand if we aren't creating chances or we don't look as though we're on the front foot and something isn't right. But the way we were playing, I think all I would have done was disrupt the rhythm of the game. And maybe upset what we were doing. There was nothing wrong with the way we were playing. We just couldn't get the breakthrough."