London Irish mounted a second-half fightback to draw with Premiership leaders Bristol Bears as both sides ran in four tries.

Two Siva Naulago efforts and scores from Piers O'Conor and Chris Vui had given the Bears a 25-point lead.

But the Exiles replied through Steve Mafi before dominating after the break.

Irish could even have snatched victory in stoppage time, but Parton's pass inside was knocked on when the hosts had a numerical advantage.

The result moves Bristol three points clear of defending champions Exeter Chiefs at the top of the table, while the Exiles climb two places to seventh.

Dramatic afternoon in west London

The match officials had a busy day, with Bristol centre Sam Bedlow fortunate to only see yellow for an early tip-tackle on Brophy Clews, who was deemed to have landed on the top of his back.

But, after Jackson's early penalty for the hosts, the Bears raced into a 14-point lead in Bedlow's absence courtesy of two interception tries.

Charles Piutau raced away to lay the platform for O'Conor's opening try and three minutes later Naulago motored the length of the field after picking off Blair Cowan's pass.

Bristol's fourth score, which put them 31-6 up, was a brilliant counter-attacking move which Piutau and Naulago worked down the left wing before the Fijian winger finished.

Yet Irish, who struggled with their line-out in the first half, were invigorated by their replacements after the break.

The Exiles had full-back Ben Loader sent to the sin-bin for a deliberate knock-on but the hosts scored through Brophy Clews and Phipps after Bristol number eight Mitch Eadie saw yellow for a shoulder charge at the breakdown.

And Parton capped a good passage of play to complete a remarkable comeback as Irish drew for the second time in the league this season.

London Irish director of rugby Declan Kidney:

"We were a pass away from winning it. Draws are always strange. We got ourselves back into contention, got a draw but nearly won.

"We talked about approaching it as if it's 0-0 all the time.

"If you have good people with the spirit our lads have, and you chip away at it, you can bring it back. It was a reasonable comeback."

Bristol director of rugby Pat Lam:

"We've worked hard to get into this situation, and the challenge for a lot of these guys are that there are targets on their backs.

"They've got to get used to not be the underdogs like they were a few years ago. To play with a big lead, they have to be even more dogged.

"You have to give a lot of credit to London Irish. We knew that would happen if we let them back into it.

"We feel like we've dropped two points, but they could also have easily won that game had that pass stuck at the end. We're fortunate to have three points."

London Irish: Stokes; Loader, Rona, Brophy Clews, Hassell-Collins; Jackson, Meehan; Goodrick-Clarke, Cornish, Chawatama, Mafi, Nott, Rogerson (capt), Cowan, Tuisue.

Replacements: Creevy, Dell, Hoskins, Munga, O'Brien, Phipps, Hepetema, Parton.

Sin-bin: Loader (57).

Bristol: C Piutau; Morahan, O'Conor, Bedlow, Naulago; Sheedy, Uren; Y Thomas, Capon, Afoa, Holme, Vui, Luatua (capt), D Thomas, Eadie.

Replacements: Kloska, Woolmore, Armstrong, Hawkins, Heenan, Kessell, Lloyd, Leiua.

Sin-bin: Bedlow (3), Eadie (61).

Referee: Karl Dickson (RFU).