I warned another trail runner about a missed turn, and he finished ahead of me. Should competition change that choice?

He ran straight past the arrow while I turned left. I shouted, "Course goes this way!" He stopped, came back, and eventually finished ahead of me.

At the finish, my friend said, "There goes your place. You should have let him work it out." I laughed, but the comment stayed with me. We'd both been near the front of a small marked-course event, and I would have been pleased with the higher finish.

I don't know how long it would have taken him to notice the mistake without me. I simply saw the turn he had missed. It felt different from giving him a tactic or telling him how to catch me.

Would you make the same call in a close race? I'm less interested in a grand statement about being a good sport than in how to accept the result afterwards without resenting a decision that felt ordinary at the time.