A crowd of almost 4,000 gave the biggest cheer of the night at Thomond Park to greet the return to action of Paul O'Connell after 250 days on the sidelines.

The Munster and Ireland star enjoyed a 40-minute runout in the second half of this floodlit All-Ireland League derby match which Shannon won by a single point.

O'Connell's appearance was his first for Young Munster since making a similar return from injury in January 2008. This time, the experience second row was lining out for the Cookies after a frustrating eight months dealing with a groin problem and subsequent complications.

And when the half-time replacement gained possession for the first time and drove at the Shannon defence he was given hearty cheers and applause as he began to make his presence felt in what was a splendid contest between these two great city rivals.

The sides defied the heavy sleet, which fell in the second half, to provide and entertaining tussle under the Thomond Park lights.

Shannon got off to an impressive start when their out-half Tadhg Bennett landed a penalty and he kicked another after Young Munster were penalised for going in at the side of the ruck.

Shannon, who had lost four of their previous five league games, were penalised for offfside in the 12th minute and from a position in front of the posts, Young Munster's number 10 Alan Kingsley made no mistake.

Despite the rising penalty count, both sides made every effort to move the ball to midfield and out wide and after another Munsters infringement, Bennett did the needful to make it 9-3 on the quarter-hour mark.

The place-kicking duel continued as Kingsley potted efforts after 18 and 33 minutes to make it all-square as half-time approached.

With defences continuing to dictate, Bennett managed to edge Shannon back in front and just before the end of a hugely enjoyable first half, Kingsley was short with a penalty attempt from near halfway.

Shannon also lost their inside centre Marcus O'Driscoll to a yellow card on the stroke of half-time, but Kingsley again failed to the shot at goal from distance and the hosts headed for their dressing room with a 12-9 advantage.

Kingsley missed a third penalty chance, two minutes into the second half, before an O'Connell-inspired drive set up an easier strike and Kingsley duly converted to atone for those three previous misses.

But Shannon showed more composure when it mattered and the influential Bennett drove them to a much-needed win, courtesy of a drop goal and the match-winning penalty.

A lay-off by O'Connell put the Young Munster backs in motion and full-back Ray Moloney got in for a try in the corner in the closing stages.

But Kingsley failed to convert and also missed a difficult penalty in the dying minutes as Shannon held on for a win which moves them off the bottom of the Division 1A table.

Scorers: Shannon: Pens: Tadhg Bennett 5; Drop: Tadhg Bennett

Young Munster: Try: Ray Moloney; Pens: Alan Kingsley 4

HT: Shannon 12 Young Munster 9