The boot of Ospreys outside half Shaun Connor had kept his battling side in touch throughout the game, leaving them only 15-12 adrift at the half-way mark and then 18-15 in arrears as the game moved into those closing 10 minutes.
It needed something special for victory and Scarlets centre Matthew Watkins provided the goods with a searing break sent full back Barry Davies racing clear for his second try. That broke the Ospreys’ hearts and replacement back row man Scott Quinnell stole over for a fourth try in injury time to provide the Scarlets’ with a bonus point and rob the visitors of theirs.
Twice Connor’s boot gave the Ospreys the lead in the first-half, but the Scarlets pack gradually won the better share of the possession and that paved the way for victory. The first of Connor’s five penalties opened the scoring before Davies grabbed the first of his two tries to grab the lead.
Three more Connor penalties put the Ospreys back in charge before the visitor’s scrum half Andy Williams was sent ot the sin-bin.
No sooner had he departed than man of the match Watkins latched onto Davies’ hopelessly awry drop goal attempt to grab a try out of nothing. Gareth Bowen added a penalty and a conversion to those two tries to give the home side a 15-12 interval lead.
The Scarlets’ Irish international Simon Easterby followed Andy Williams into the sin-bin early in the second half for killing the ball after a blistering attack from Shane Williams and Connor and Bowen swapped penalties to make it 18-15.
Then came Watkins’ moment of magic, and that late charge from Quinnell, to make it a perfect night for the Scarlets who moved a point clear of Ulster at the top of the table. For the Ospreys, meanwhile, this was a seventh successive defeat.