Arsenal had already hit the woodwork through Jack Wilshere and Aaron Ramsey at the Emirates Stadium when Boruc attempted to outwit Olivier Giroud with some fancy footwork inside his penalty area in the 22nd minute.
The Poland international attempted one drag-back too many, however, enabling Giroud to steal possession and stab home the opening goal.
Giroud made sure of victory with four minutes remaining, registering his 10th goal of the season from the penalty spot after Jose Fonte had been penalised for pulling Per Mertesacker’s shirt.
Victory left Arsenal four points above second-place Liverpool, while Southampton remain third but will slip off the podium if Chelsea avoid defeat at West Ham United in the day’s late game.
Earlier, Daniel Sturridge came off the bench to earn Liverpool a 3-3 draw against Everton with an 89th-minute equaliser in a frenetic and richly entertaining Merseyside derby at Goodison Park.
A brace from Romelu Lukaku had put Everton on the brink of a first win over their city rivals in seven matches, but Sturridge’s header gave Liverpool a share of the spoils after a breathless encounter.
“It was a terrific game. I’ve been involved in a few and they are real heart-stoppers,” said Liverpool manager Brendan Rodgers.
“We again showed our resilience and ability to fight back. This is a difficult place to come and they haven’t lost at Goodison Park this year.”
Philippe Coutinho’s fifth-minute opener for Liverpool was swiftly cancelled out by Kevin Mirallas, before Luis Suarez restored the visitors’ lead in the 19th minute by bending a 25-yard free-kick into the bottom-right corner.
Mirallas was fortunate to avoid a red card for a knee-high foul on Suarez before half-time, but he teed up Lukaku for both the equaliser and the 82nd-minute header that put Everton in front.
Everton would have moved level on points with Liverpool if they had won, but Sturridge had the final say when he smartly headed past Howard from a Gerrard free-kick.
Everton manager Roberto Martinez said: “It’s really disappointing we didn’t get three points. To concede late on from a dead-ball situation doesn’t reward my team for how they played in the second half.”
Freshly-appointed Crystal Palace manager Tony Pulis watched from the stands as his new side survived the dismissal of Yannick Bolasie to win 1-0 at Hull City.
Bolasie was sent off for a clumsy challenge on Jake Livermore in the 78th minute, but Barry Bannan scored from a Cameron Jerome cut-back three minutes later to give Palace a first away win of the campaign.
Victory at the KC Stadium took Palace off the foot of the table at the expense of Sunderland, who went down 2-0 at Stoke City.
Charlie Adam and Steven Nzoni scored in either half for Stoke, while Wes Brown was sent off for a seemingly clean challenge on Adam in the 36th minute, provoking a furious reaction from Sunderland manager Gustavo Poyet.
Fulham remain in the bottom three after losing 2-1 at home to Swansea City, for whom Jonjo Shelvey claimed an 80th-minute winner after Scott Parker had cancelled out an own goal by Fulham centre-back Aaron Hughes.
Meanwhile, France forward Loic Remy found the net for the eighth time in eight league games as Newcastle United won 2-1 at home to Norwich City.
Yoan Gouffran was also on target for Newcastle, with Leroy Fer replying for Norwich, as Alan Pardew’s side moved to within a point of the Champions League places after a third consecutive victory.