AITA for benching our new goalkeeper for the second half after promising equal playing time?

I took the orange goalkeeper shirt from my friend Rob at halftime and handed it to Ellis. Rob said, "I thought we were doing a half each."

That was the plan. Our seven-person five-a-side group had agreed that Rob and Ellis would each spend fifteen minutes in goal, then play outfield for the other half. Rob is new to the group; Ellis has played with us for years. I organize the booking and make the substitutions.

We were losing 3–1. Rob had let in one shot I thought he should have reached, but we'd also given the other team plenty of space. Instead of moving him outfield as promised, I put Ellis in goal and kept Rob on the sideline so our strongest five could try to catch up.

I told Rob I'd give him more time next week. He had paid the same $12 as everyone else and had already spent his fifteen minutes in goal. He said he hadn't come just to watch the second half.

We lost 4–2 anyway. Rob left his shirt folded by the bench and hasn't answered the next booking message. Ellis thinks I made the sensible decision during a close game. Another teammate says we never agreed that winning would override the rotation.

I wanted us to have a chance to recover, but I changed the deal for the least experienced person without asking him. AITA for making that call?