Portadown had defender Keith O'Hara red-carded late on at Coleraine but still came away with a share of the spoils.
Referee Arnold Hunter showed 12 yellow cards in a game that was far from bad tempered although still keenly contested.
Coleraine keeper Michael Doherty made a couple of excellent saves on his first appearance back at the club he left two years ago for Institute.
The Ports could have been in front from their opening attack. Sean Mackle was left unmarked and cut in from the left flank to clip a shot across the face of goal.
Coleraine responded with a slick approach involving Ian Parkhill, Ruairi Harkin and debutant Mark Miskimmin. The new arrival from Glentoran fired in a cross from the left for ex-Ports man Joe McNeill to rifle a rising shot just over the bar.
The Bannsiders, buoyed by back-to-back victories after a slow start to the season, posed a credible threat with inventive, intelligent approach play.
But it took a headed clearance from defender Johnny Watt to ensure Coleraine did not concede when Tim Mouncey glanced a header on target from Chris Casement's corner.
Then, when Shane McGinty released Miskimmin on the right side of the penalty area, the striker elected to play the ball inside rather than take a shot and the opportunity passed.
Parkhill headed McGinty's cross the wrong side of an upright and but for the brilliance of keeper David Miskelly, the visitors would have gone in behind.
McGinty's stunning shot was pushed away by the stopper. The ball fell for Harkin whose follow up was diverted away from goal by the keeper's outstretched foot.
Portadown's high tempo start to the second half almost paid instant dividends for Mark McAllister. A long ball over the top was missed by defender Aaron Canning leaving the striker with only Doherty but his shot was tame.
Former Linfield skipper Michael Gault made his league debut for Tim Mouncey and picked up a booking within 10 minutes for a tangle with Harkin which also saw the Coleraine man cautioned.
Miskimmin was denied a header on goal by the alert Keith O'Hara when Coleraine defender Watt floated over a teasing cross from the left side. Veteran O'Hara kept his eye on the ball to head it away from danger.
Doherty was at full stretch to fingertip Garry Breen's 82nd minute headed attempt over the crossbar.
O'Hara was harshly booked for a second time and subsequently dismissed four minutes later for a challenge on Miskimmin.
Coleraine sub Gary Browne directed a late header at Miskelly while Harkin headed a Breen effort off the line in a period of sustained Portadown pressure as they tried to claim the winner.