The Bees had taken the lead on 77 minutes through the brave persistence of Richard Graham who capitalised on a Rovers' defensive mix-up. The visitors, however, went home with a point through a late Agogo effort, after he rose unchallenged at the back post and netted from close in.
Barnet made their intent clear from the off, and were unlucky not to have taken the lead in the opening two minutes. The dangerous Graham found Dean Sinclair from the left, with Sinclair teasing his way past the Rovers defence only to see his 10-yard effort tipped acrobatically over the bar by an alert Scott Shearer.
The Bees sustained their pressure and went close again on 10 minutes when Sinclair drove a fierce angled shot which flew past Shearer's post.
Midway through the first half, Dwane Lee created space on the right and his measured low cross was unable to find the tap-in it needed.
Rovers' only effort of the first half saw Craig Disley flash a shot wide from 12 yards and his side were indebted to Jo Bass for the half ending goalless, when he cleared a Ben Strevens header off the line.
Barnet's crossing game was finally rewarded when a punt out from keeper Scott Tynan found a willing Graham and, despite pressure from Shearer, Graham was gifted his first strike of the season as his effort trickled in.
That seemed to be it, however, the Pirates secured a point when a defensive mix-up involving Ian Hendon and Ismail Yakubu was punished when a Ryan Williams cross was headed in by Agogo.