Posh's miserable festive run under current boss Barry Fry continued as David Farrell missed a glorious chance to kill off Grimsby and lift them clear of relegation trouble.
The second division strugglers haven't won a fixture over the Chirstmas period since Barry Fry's first season in charge in 1996, but the run seemed set to end when David Farrell burst through on goal midway through the second half.
The 31-year-old latched on to a Steve Thomson through ball and cut inside defender Michael Edwards only to fire a shot high and wide with the goal at his mercy.
That was the best chance of a dour struggle with enough to persuade Barry Fry to dip into the transfer market in the near future.
He said: "To be honest, I thought we never looked like scoring and its time now to freshen up all areas with a few new face.
"David should have done better but, don't forget, he created the chance for himself and was the only man on the pitch capable of doing that." Posh had threatened in just the second minute when Mark Arber's header from an Andy Legg corner was nodded off the line by defender Greg Young.
Grimsby survived another close shave 10 minutes before the interval when Tony Crane produced another last ditch block after home captain Curtis Woodhouse had prodded the ball past keeper Aidan Davison from close range.
Grimsby began the second half brightly with both Iffy Onuora and Stuart Campbell both seeing shots blocked in a hectic goal mouth scramble. But it wasn't until the 75th minute they forced home keeper Mark Tyler into his only noteworthy save when he was called upon to block a venomous shot from leading scorer Mick Boulding.
Grimsby chief Paul Groves said: "It certainly wasn't a classic and I can't imagine there was too much excitement for the supporters. But I can't complain at another hard-earned point after the determined defensive performance."