TUNBRIDGE WELLS recovered from their defeat to Bedford and made inroads into the points difference with the teams in the top half of London and South-East Premier Division.
CS Stags were promoted last year and had already taken the scalp of Wimbledon, the league leaders.
They sat in 11th spot in the table, one position below Wells, so this contest was important for both sides.
Wells started strongly but were unable to turn the pressure into points, and after five minutes the Civil Service side made a break and Wells were penalised for offside in front of their posts, a kick which CS converted.
Wells fought straight back and after several attacks they were awarded a penalty that Frank Reynolds slotted.
Strong running from the back row of Dave Allen, Mike Hathaway and Nick Doherty finally paid off when Doherty picked up from the base of a ruck and powered over for Wells’ first try, converted by Reynolds.
On the brink of half-time the home side produced more strong phases of play, with Stu Nicholls hitting Christian Earle in the lineout.
George Montgomery skipped around the defence to touch down under the posts. Reynolds added the extras.
The referee then added eight minutes of injury time at the end of the first half and Stags scored in the corner in 48th minute to make it 18-8 at the interval.
They started the second half much stronger but Wells’ defence held firm and they were soon back in attack.
From a lineout on the 22 they caught and drove as a unit, and Allen touched down from a powerful forward effort, Reynolds again converting.
CS were not about to give up, and when Wells lost prop Ben Williams to an injury it was a key point in the game.
The visitors pressurised Wells in the scrum and were finally rewarded with another try which they converted.
They followed that up with another penalty to put them seven points from snatching victory, but Wells held firm to close out the valuable win.
It was a fine all-round performance which included an impressive debut for Anthony Storkey at scrum-half.
Tunbridge Wells now travel to Chingford on Saturday [November 24, kick-off 2.30pm].