On a day when Championship leaders Southampton lost at Bristol City and fellow promotion chasers Leeds and Blackpool dropped points, Boro were presented with an ideal opportunity to enhance their place in the league table.
A win would have moved Tony Mowbray's side level on points with third-placed Cardiff City going into tomorrow night's game with high-flying West Ham United at the Riverside, but instead the Boro boss was left frustrated and disappointed.
For some, it might still be too early in the season to take much stock from the league standings, but with the Saints and the Hammers threatening to pull away from the chasing pack, it is crucial Boro to capitalise on such opportunities. This was their eighth draw of the season.
Matthew Bates gave the visitors a 57th minute lead when he towered above everyone to head home Tony McMahon's corner, but a stunning strike from Paul Taylor with nine minutes remaining meant Boro left London Road two points worse off.
Both before and after Bates' opener, Boro had enjoyed a succession of chances and Mowbray admitted that for the second game in a row, his side's inability to kill games off had cost them.
"I'm frustrated, the dressing room is frustrated. It's another day when two points slipped away," Mowbray said.
"The frustration was we didn't take one of the chances that came our way to finish the game off.
"The team are applying what we work on in training and there were plenty positives. You want to score every time you attack, but it's not the case.
"The second goal would have killed the game off, but credit to them, they kept going and tried to find the answers and ultimately they got a point.
"I think in the first half we were totally in control of the game and I can't remember them threatening our goal.
"I couldn't see them scoring to be fair. They're a team that scores so many goals, yet they were struggling to find an answer to the conundrum to the way we set up at the back.
"Ultimately, they did by being a bit more direct, and as I say it's disappointing but maybe the answer to why we never got all the points was that we didn't take our chances at the other end, rather than conceding a late goal."
As they had been back in August when they were 2-0 winners at London Road in the Carling Cup, Boro were firmly in control of Posh, creating a string of decent chances.
In-form Scott McDonald enjoyed the best chance of the first half. A brilliant, defence splitting through ball from Joe Bennett sent the striker through, but his touch as he attempted to lift the ball over Paul Jones was heavy and the ball went wide.
After Bates had given Boro the lead, Faris Haroun and Marvin Emnes both saw brilliant chances to finish the game off disappear when their angled low shots ran inches past Jones' post.
As expected, going behind sparked Darren Ferguson's side into action, Jason Steele denying George Boyd with a brilliant save, while Tom Kennedy saw his fierce strike crash off the post.
Then as the clock ticked down, the inevitable happened and it was a fabulous piece of skill that drew Posh level against a nervous Boro side that had looked so comfortable for an hour of the game.
Barry Robson conceded a free-kick and from the resulting ball, Stephen McManus could only half clear with a header that fell to Taylor, who struck a superb first-time angled volley past Steele into the top corner.
Given how solid Boro have been defensively this season, the manner in which the goal was conceded was a bitter pill for Mowbray to swallow, who admitted his side should have done better.
He said: "We've had a few words about dealing with the ball but I don't want to overplay it.
"Teams shouldn't be able to knock a 60-yard ball into the corner then the cross doesn't get dealt with. The players are disappointed, they will know they can see those situations out and generally we do and had done all day and yet when the ball ends up in the back of the net you go back to it and say you could have done better.
"That's football, we are disappointed to finish the game that way. We've got to go and beat West Ham and if we beat them on Tuesday night, people say a point away from home isn't so bad if you win your home games."
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