Canterbury's season hangs by a thread after they fell at the last hurdle in an unforgettable clash with the Sydney Roosters at Allianz Stadium on Friday night.

Chasing the biggest comeback win in their history after mowing down a 22-0 deficit to take a 28-22 lead, the seventh-placed Bulldogs had their hearts broken when Michael Jennings got across the line with five minutes remaining to snatch the points for the home side in front of 13,589 fans.

Canterbury had just about everything going against them heading into the match. Coming off a five-day turnaround following a disappointing two-point loss at home to Cronulla which cost them a serious injury to Josh Reynolds - and losing Frank Pritchard and Curtis Rona to injury shortly before kick-off - there seemed little they could do stop an unchanged Roosters side coming off a seven-day break.

And it stuck to that script in the first half an hour when the Roosters flew out to a four-try lead.

However, by the 52nd minute Canterbury had evened the ledger and, three minutes later, with replacement winger Corey Thompson's second try, they hit the front.

It set up a pulsating final half hour. With 12 minutes remaining, on the back of brutal charge by forward Jared Waerea-Hargreaves, Blake Ferguson avoided the sideline by a millimetre to score for the Roosters and James Maloney's attempted conversion hit the post, leaving the gap at two points.

The critical moment came with five minutes remaining when Mitchell Pearce - celebrating his 200th appearance - grubbered through, Sam Perrett gambled on it going dead, and Jennings snuck through to ground the ball. The conversion made it 32-28.

On the stroke of full-time, Jackson Hastings pounced on a Greg Eastwood mistake to score.

It was a big effort by the Bulldogs but they now face matches against Brisbane in Brisbane and then Souths a fortnight later to force their way into the finals.

The Roosters' early lead seemed destined to put them on track for a big win. However Canterbury launched a stirring response that left them behind by only six points at the break.

The home side's early flourish came with three tries down the left edge. The first came when Daniel Tupou touched down after Perrett was turned around by a pin-point Pearce grubber.

Roger Tuivasa-Sheck then got on the outside of Trent Hodkinson to score after some efficient lead-up work by the Roosters forwards left him with a one-on-one.

Tupou then grabbed his second at the end of a keep-the-ball-alive play that went through numerous sets of hands and ended with the big winger snapping up a cross-field kick by Maloney. And they crossed over yet again when a series of quick offloads ended with Maloney dishing off to Jennings to score under the posts.

It looked a done deal after just half an hour, but the Bulldogs woke up. In the space of just 16 minutes they scored three times, including two to players who came in as replacements.

Firstly, Shaun Lane - who came in side for Pritchard - crossed over before Josh Morris reached out to score in almost exactly the same spot as Lane down the left edge.

Then Thompson, in for Rona, scored in the left corner nearing half-time, shortly after Roosters forward Sam Moa left the field with a dislocated wrist.

The Bulldogs had all the momentum going into the second half and the scores were locked up when Hodkinson forced his way over in the 50th minute.

Five minutes later the Bulldogs took the lead when Moses Mbye put a pass over the top to Thompson who got across for his second try.