McCann is nursing a strained right quadriceps muscle that he injured running the bases in the fourth inning of Wednesday's game against the Florida Marlins. He stayed in the game, driving in a run in the six-run seventh-inning rally, but then left the game and sat out Thursday's series finale. He had hoped to play Friday.
"My quad feels better," McCann said, who took ultrasound treatments and did some stretching Friday afternoon. "Bobby decided to play [Ross] but I'll be there for a pinch-hit or be there late. I felt I could [play]. I'd have to take it easy on the bases, but other than that I feel good."
That wasn't good enough for Cox, who chose to give McCann another day of rest.
Cox's discretion opened the door for Ross, who is hitting .265 with eight RBIs and a .390 on-base percentage in 10 starts this season.
"I'm definitely a backup catcher, and I've got a backup role, but the days I'm starting, I'm a starter," Ross said. "I'm starting today, I started yesterday. I'll go out there and I'm going to do the best I can in my at-bats and call the best game that I can, do my homework on calling the game, and give it the best I've got when I play. If that's once a week that's great. If it's twice a week or if [McCann] goes down and I play 15 in a row like I did last year, that what I'm here for.
"For the long haul, it's best if [McCann] gets healthy, even if we're a man short per se, and I'm in there instead of him. But it's just one of those things. I just go out and my mindset is to do the best I can to help the team win."
Ross wasn't sure he'd be in the lineup Friday following Thursday's marathon, which included a 77-minute rain delay.
But once that was confirmed, the ever-ready Ross, who played in his 500th career game on Wednesday night, had a different challenge to get used to -- the big crowd of reporters around his locker.
"I thought I got traded!" Ross shouted to teammate Eric Hinske, then laughed. "I thought, 'Dang! As soon as I start playing good.'"