George Ford kicked three late penalties as leaders Leicester survived a scare against London Irish to preserve their 100% Premiership record.

Paddy Jackson was flawless for the Exiles, with three penalties, as well as converting an Agustin Creevy try.

But it was not enough to earn Irish a first win of the season.

Instead, Nic Dolly and Hanro Liebenberg both crossed the line to secure Leicester's fourth straight victory.

In a tentative opening, it was Irish who applied initial pressure but the Tigers' defence held firm as the visitors gradually gained the upper hand.

Although promising breaks by George Martin and Harry Potter came to nothing, Dolly broke the deadlock in the 19th minute, burrowing through from the back of the maul to dot down his fourth try of the season.

However, Ford's conversion attempt was off target and the fly-half also miscued what looked a routine penalty from 25 yards, in between two successful kicks by Jackson that earned the Exiles a narrow half-time lead.

Jackson was handed the opportunity to stretch that advantage just five minutes into the second half when Tommy Reffell was penalised - and the Ulsterman made no mistake from 40 yards.

That prompted a double change in the Tigers' pack, with new signing Marco van Staden introduced alongside Julian Montoya and the latter was immediately involved in the move that nudged his side back in front.

Montoya's efforts in the driving maul set up the opening for Liebenberg and the second-rower dived over close to the breakdown, with Ford nailing the conversion to put Leicester 12-9 ahead.

The Exiles responded straight away, winning two penalties in quick succession and veteran hooker Creevy broke clear from the back of the maul, storming over for a try that Jackson converted.

But Ford landed a 35-yard penalty to reduce the deficit and then kept his nerve with two further successful kicks in the final 10 minutes as Leicester made it four wins from four and regained top spot in the table.

London Irish head coach Les Kiss told BBC London 94.9:

"For the most part, our kicking and the pressure plan worked well. In that second half, though, there was a five or eight-minute period where we just didn't back ourselves.

"We could have said 'let's carry this ball a little bit more, make them make decisions around the tackle area and believe what we have can take Leicester to a place they don't like.'

"We've got to keep backing our game in those situations, not being afraid to go for it. But the effort was fantastic, they certainly played with heart.

"We did give a couple of penalties away at important times. We're not an ill-disciplined team but there were some critical moments where we put ourselves under pressure and that hurt us."

Leicester Tigers head coach Steve Borthwick told BBC Radio Leicester:

"That could have gone either way at the end - it was a tight game and it could have been a loss. London Irish are a really good team and I thought tactically they were excellent.

"The fact is, the players showed immense character and fight and if it had been a loss, I'd still have been very proud of them.

"The players had to work some things out on the pitch and adapt towards the end. We had a couple of knocks and we had to rejig the back line.

"You've got to adapt and find a way to overcome things and the players did that against a really tough team."

London Irish: Parton; Loader, Rona, Hepetema, Hassell-Collins; Jackson, Phipps; Goodrick-Clarke, Creevy, Van der Merwe, Mafi, Coleman, Rogerson (capt), Donnell, Tuisue.

Replacements: Cornish, Dell, Hoskins, Simmons, Nott, O'Brien, O'Sullivan, Van Rensburg.

Leicester: Steward; Potter, Scott, Socino, Nadolo; Ford, B Youngs; Genge (capt), Dolly, Cole, Wells, Green, Martin, Reffell, Liebenberg.

Replacements: Montoya, Leatigaga, Heyes, Snyman, Van Staden, Wigglesworth, Burns, Porter.

Referee: Adam Leal (RFU).