Heffernan was sent off after headbutting Shrimpers defender Charlie Mulgrew with three minutes of the Roots Hall first-leg clash remaining.

The striker will now miss next Friday's second leg at the Keepmoat Stadium and a potential trip to Wembley for his moment of madness.

"I didn't see it but I spoke to the referee and he said it was a headbutt and we have to accept that," said manager Sean O'Driscoll.

"It's disappointing for him, he's going to miss three games and he's devastated in the dressing room now. But he's got to take it on the chin and move on."

Rovers will now be favourites to progress, although they could have taken a priceless lead back to south Yorkshire had Jason Price not fluffed his lines in front of goal in the second half.

Price was put clean through, one-on-one with Darryl Flahavan, but the Southend goalkeeper stood up well and kept out his low shot.

Southend had their chances too, not least a point-blank Simon Francis effort kept out by veteran Rovers goalkeeper Neil Sullivan just before the interval.

The Shrimpers laid siege to the Doncaster goal following Heffernan's dismissal but Nicky Bailey, James Walker and Lee Barnard could not make the breakthrough during four minutes of stoppage time.

"Southend showed they are a good side and I'm sure the game next week will be just as tight," added O'Driscoll, who lost player of the year Richie Wellens to a hernia problem prior to kick-off.

"We had a spell in the second half where if we had got a goal we would probably have got on top but you have to give them some credit.

"The sending-off meant it was backs to the wall for the last five minutes but they are a good side. One defeat in 15 bears testament to that and it will be a tough game at home.

"I think all 22 players deserve a pat on the back. It was a tight game."

Shrimpers boss Steve Tilson said: "It was a fair result on the night. We probably shaded the first half and they shaded the second. The main thing is we are still in the tie.

"We would have liked to have had an advantage but it's all to play for in a one-off game now."