Ryan Brunt put Tranmere ahead in the 33rd minute of Saturday's League One clash at Prenton Park as he flicked a speculative overhead shot by Martin Devaney out of the reach of Addicks goalkeeper Ben Hamer and inside the far post.
Charlton equalised after an hour when Michael Morrison headed in off the underside of the crossbar from a Dale Stephens corner.
"It was a good point for us in our quest to move up," said Powell. "On the balance of play we could have nicked it. But we did well to come back after conceding a poor first-half goal.
"It is always tricky to come here. Tranmere make you work hard for anything. I asked for more at half-time and we stepped up. I've got to give the players credit for that. We were in the ascendancy in the second half but we had to concentrate.
"We had to be on our guard. I think 1-1 is fair enough but I felt we could easily have had a penalty. I've seen the incident twice now and am more and more convinced. But the referee only has one look and didn't give it."
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