Brentford and Cheltenham had to settle for a share of the spoils in this highly charged Division Two encounter at Griffin Park.
The Robins opened much the brighter and on 10 minutes a Grant McCann free kick into the box was met by Duff and his header was easily claimed by Paul Smith, then almost immediately Mark Yates fired wide from 25 yards.
Cheltenham were taking the game to Brentford and the home side were unable to mount a worthwhile attempt on goal.
On the 20 minute mark a Martin Devaney effort on the edge of the box was saved by Smith. Three minutes later the Robins opened the scoring when the referee adjudged that Leo Roget had pushed John Brough in the box following a cross from the right and McCann stepped up to calmly stroke home the resultant spot kick.
On the half hour mark a Roget back pass fell well short of keeper Smith which left Marvin Brown in the clear, his cross from the left found Devaney who scored easily from close range to extend the Robins' lead.
A minute from the break Rowan Vine for the home side was yellow carded for a foul on Jamie Victory.
During the break Bees manager, Wally Downes kept his players on the pitch.
Three minutes after the break Brough fired high over the bar from the edge of the box and two minutes later Roget cleared Brown's effort off the line after Smith failed to gather a cross.
On 63 minutes the Bees pulled a goal back when a Martin Rowlands corner was met by Michael Dobson in the six yard box and his header easily beat the keeper.
On 74 minutes the game erupted when Bees' defender, Roget, and Robins' substitute Julian Alsop, who had only been on the pitch for eight minutes, were both straight red-carded for fighting near the by-line. Play was held up for four minutes while both players were escorted off the pitch. The Bees equalised on 78 minutes when trickery by Steve Hunt on the by-line left two defenders for dead and his cross from the left was met by sub O'Connor who headed home from a couple of yards out.
On 82 minutes the Robins had a great chance to regain the lead when McCann's low cross from the left found sub Damian Spencer only six yards out but he ballooned the ball high over the bar.
Eight minutes of additional time was added on by referee Mr Stretton but neither side could take all three points and in the end they settled for a point apiece.