Northampton held off a spirited London Irish comeback to win and maintain their 100% start to the season.

Paddy Jackson had a chance to snatch victory for Irish in added time but his attempted drop-goal went wide.

Saints scored early tries through Tom Collins and Matt Proctor before Irish replied through Agustin Creevy, a penalty try and Tom Parton.

There was a nervy wait for Saints to secure the win after Irish fly-half Jackson missed his drop-goal while television match official David Rose cast his eyes over a suspected no-arms tackle by Courtney Lawes.

But the decision went in the hosts' favour and Irish's wait for a Premiership win now stretches back to nine matches after beginning this term with two defeats and a draw.

They looked like ending that six-month wait for a victory when full-back Parton crossed for their third try to give them the lead on 63 minutes.

Saints fly-half Biggar's third penalty with six minutes to play won it after they failed to capitalise on a first half that saw two early tries from winger Collins and centre Proctor.

But Irish hooker Creevy's try under the posts shortly before the break from a rolling maul gave them some momentum despite trailing 17-7.

They built on that after Api Ratuniyarawa and Paul Hill were sin-binned for Saints with Hill's illegal collapsing of a maul resulting in a penalty try for the Exiles.

Saints did not concede any more points despite being temporarily reduced to 13 men and Biggar slotted his second penalty from 40 metres out on the hour to calm nerves at 20-14.

However, when Ollie Hassell-Collins burst past two attempted tackles before setting Parton free to his right, the hosts needed to dig in to secure their third win of the campaign.

Albert Tuisue's off-the-ball infringement at a scrum saw Irish concede the penalty that allowed British & Irish Lion Biggar to mark his return to club colours with a winning contribution.

Northampton Saints director of rugby Chris Boyd told BBC Radio Northampton:

"The only good thing out of today is that we can take the four points and the performance from the first 15 minutes, which was pretty decent.

"We were determined to give back the 'get out of jail card' we were handed. I had to apologise to Declan Kidney for that performance and that we came away with the win.

"After three games, the fact we're still 100 per cent off the tee from the three guys who've kicked, that's probably helped get us over the line a couple of times.

"We've got a history of being inconsistent, we're consistently inconsistent. On a different day, with a different set of circumstances, we'd play a lot better than that and lose.

"But really, it's not good enough. Some of the penalties we gave away were ludicrous and we can't keep allowing teams to stay in the game."

London Irish director of rugby Declan Kidney:

"We have to look at our starts and indeed our last quarter where we conceded too many penalties to put us under pressure.

"We do everything as a collective and there were lots of marginals that went against us in the closing stages and nobody likes giving away penalties.

"We had to work hard to create the tries and Northampton are a resilient side, but again we went 17-0 behind early and made things hard for ourselves."

Northampton: Furbank; Sleightholme, Proctor, Dingwall, Collins; Biggar, Mitchell; Auterac, Matavesi, Hill, Coles, Ratuniyarawa, Wood, Ludlam (capt), Augustus.

Replacements: Fish, Waller, Painter, Moon, Lawes, Harrison, Lomani, Tuala.

Sin-bin: Ratuniyarawa (44 mins), Hill (46 mins).

London Irish: Parton; Loader, Rona, Van Rensburg, Hassell-Collins; Jackson, Phipps; Goodrick-Clarke, Creevy, Hoskins, Simmons, Coleman, Rogerson (capt), Donnell, Tuisue.

Replacements: Cornish, Dell, Van der Merwe, Nott, Mafi, O'Brien, White, Williams.

Referee: Tom Foley (RFU).