The scene was set for Munster’s leading scorer to steal the match, and Jeremy Staunton held his nerve to slot over the winning kick from 25m.
Thomond Park exploded with relief. Munster have now moved into the top half of the table.
The game began well for the current Celtic champions, Staunton landed an early penalty and then converted Mike Mullins’ 15th try for a 10-0 lead.
But the Warriors hit back on the half-hour with a well-constructed try scored by prop Phil Booth near the posts and Jenkins converted for 10-7.
Staunton and Jenkins then exchanged penalties and
Munster were 13-10 in front at the break and playing into the strong wind.
Within 90 seconds of the re-start the Warriors levelled with a Jenkins penalty only for Staunton to edge the Irish in front again with a successful kick at goal.
This only served to stir the Warriors. When Shaun James set up speedy wing Aisea Havili for the Warriors’ second try, the Welsh were in front 18-16.
But true to the form of the match Munster’s noses were soon in front once more when Staunton kicked a penalty after 53 minutes, and, as the ding-dong battle continued, Jenkins edged the Warriors back in front at 21-19 three minutes later.
Fine defence from both sides meant there was no further scoring until Staunton emerged as the Munster hero with his match winning penalty