Tranmere Rovers drew 1-1 at Brisbane Road and despite opening up the home side after half-time they couldn’t put away enough of their chances to take victory back to Merseyside.
Rovers are now four points behind leaders Macclesfield but Mellon knew how demanding this fixture was for his players.
“I think we have had four chances (in the second half) that on any given day you will be disappointed not to take,” he said.
“If you create those chances, you have got to take them and we didn’t so that was the tale of the game.
“Before we arrived I knew this was going to be a difficult game. It was two teams going at it, but I don’t think anyone in the stadium could say we didn’t have most of the chances.”
Mellon added: “I think you have to respect a point coming here at any stage of the season. They have a very good manager and it’s just a pity we didn’t take one of a number of one-vs-one opportunities that we made.
“Apart from not putting the ball in the back of the net we have played well.
“All credit to the boys. We have taken four points from a possible six from Leyton Orient this season and that’s not a bad total.”