|London Irish (15) 25|
|Tries: Narraway, Maitland, penalty try Cons: Noakes, Geraghty Pens: Noakes 2|
|Northampton (8) 23|
|Tries: K Pisi, North, Fotuali'i Con: Myler Pens: Myler 2|
|Relive Boxing Day's Premiership action|
London Irish recorded their first Premiership win of the season through a late penalty try against Northampton.
First-half tries from Luke Narraway and Sean Maitland had given London Irish a 15-8 lead at the break, with Ken Pisi crossing for the visitors.
George North and Kahn Fotuali'i tries put Northampton ahead and gave Jim Mallinder's side a five-point lead going into the last quarter.
But Irish stole victory after referee Ian Tempest penalised Saints late on.
Tom Coventry's side looked set for a seventh defeat in seven league games when winger Asaeli Tikoirotuma was sent to the sin bin for a poorly-timed tackle on Ben Foden with 15 minutes remaining.
But the hosts weathered Northampton's attacks despite being a man down and repeatedly kicked for touch and the corner in a bid to snatch victory.
Their patience was eventually rewarded after Jamie Gibson was shown a yellow card for failing to release Ofisa Treviranus.
The following scrum and drive led to the decisive penalty try as referee Tempest punished the Northampton pack for pulling the drive down.
Shane Geraghty kicked the simple conversion before Stephen Myler saw a late drop-goal attempt charged down in the closing seconds.
Irish move off the bottom of the table after Newcastle's defeat at Leicester while Northampton fell to their fourth defeat of the season, but a first in three games.
London Irish head coach Tom Coventry said:
"I haven't had a lot to smile about. It was a good sign that we could battle it out as we have been rolling over against other sides, but we showed a lot of backbone today.
"It was like Christmas Day today as we showed a lot of Christmas spirit to get there in the end.
"It was a definite shot in the arm as it's been a tough time and will give us a lot of confidence."
Northampton director of rugby Jim Mallinder said:
"We never really got into our game, we gave away too many soft penalties and they kept it simple and did the basics better than us.
"The referee went a bit early with the penalty try award, but we've no complaints.
"We've been inconsistent all season and have not been firing on all cylinders."
London Irish: Maitland; Lewington Hearn, Williams, Tikoirotuma; Noakes, McKibbin; Court, Paice, Franks, Symons (capt), Lloyd, Narraway, Cowan, Treviranus.
Replacements: Stevens, Smallbone, Aulika, Sinclair, Trayfoot, Steele, Geraghty, Mulchrone.
Northampton Saints: Foden; K Pisi, G Pisi, Burrell, North; Myler, Fotuali'i; E Waller, Hartley (capt), Hill Paterson, Day, Lawes, Gibson, Harrison.
Replacements: Haywood, A Waller, Denman, Matfield, Dickinson, Dickson, Hanrahan, Collins.
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