A second-half volley from the Welshman added to Santi Cazorla's opener to cap a superb day for the league leaders, with Chelsea also losing to Newcastle earlier in the dayArsenal beat Liverpool 2-0 at the Emirates Stadium on Saturday to extend their lead at the top of the Premier League to five points.
Arsene Wenger's men had gone into the game on the back of a Capital One Cup defeat to Chelsea but bounced back to open up a healthy advantage over the chasing pack in the league, especially pertinent following their London rivals' 2-0 loss at Newcastle United earlier in the day.
Arsenal made no mistake in underlining their title credentials at the Emirates as they produced a dominant performance to secure victory.
Santi Cazorla opened the scoring as he pounced on a rebound after heading Bacary Sagna's right-wing cross against the post following a fine counterattack from the hosts.
Liverpool had spells of pressure at various points in the match but Arsenal killed things off after 59 minutes, when Aaron Ramsey collected a square pass from Mesut Ozil on the edge of the area before unleashing a magnificent volley to all but the end the game as a contest.
|VIEW FROM THE EMIRATES
|By Liam Twomey at the Emirates Stadium
"The result of this match was always going to be interpreted in the light of these two sides' burgeoning title credentials and, at the whistle, it is Liverpool's challenge which has taken a dent.
"If Santi Cazorla's goal was the reward for excellent persistence and composure, Aaron Ramsey's 30-yard screamer was a monument to the unbridled confidence flowing through this Arsenal team at present. If awards and trophies were given out in November this season would belong indisputably to the flying Welshman and his team but, eight years into a debilitating trophy drought, Arsene Wenger knows better."
Brendan Rodgers, meanwhile, made just one change to the Liverpool side that beat West Brom 4-1 in their previous Premier League clash, as Jon Flanagan replaced Glen Johnson to make his first start of the season at wing-back.
Arsenal created the first chance after five minutes, Liverpool goalkeeper Simon Mignolet producing a good save to deny midfielder Rosicky from close range following neat build-up play from the hosts.
Liverpool dictated possession for much of the early stages - yet it was Arsenal who went ahead 19 minutes in as Cazorla showed great reactions to fire past Mignolet after initially hitting the woodwork.
Wenger's men looked to press home their superiority following the goal, Cazorla's long-range drive forcing another strong stop from Mignolet, who was called into action again to prevent Ramsey from doubling their advantage soon afterwards.
Cazorla was at the centre of the majority of Arsenal’s attacks and the Spain international wasted another opportunity to increase the lead when he dragged a poor shot wide of the right-hand post just before half-time.
Liverpool went close to levelling in the early stages of the second half, however, as midfielder Jordan Henderson fired narrowly over the crossbar following good work down the right from Luis Suarez, who played well considering the furore surrounding his potential move to the Emirates this summer gone.
But the visitors were fortunate not to concede a second as Olivier Giroud somehow shot wide after a mistake from Kolo Toure had allowed the France international striker to race through on goal.
Rodgers' men did not learn from that let off, though, and were duly punished a few minutes later, Ramsey shooting past a helpless Mignolet with a sublime volley.
Liverpool threatened an unlikely comeback in the closing stages, Suarez twice spurning glaring opportunities and Wojciech Szczesny denying substitute Philippe Coutinho - but Arsenal saw out a deserved victory and are now five points clear at the top of the table.