The Scottish side have now won four from four but they had their man of the match Watson to thank for the victory at BT Murrayfield.

The flanker crossed for the decisive second-half try and then claimed two superb turnovers in the closing stages of the match as the visitors pressed for a winning score.

Two Greig Tonks penalties to one from Peter Nelson sent the home side in 6-3 ahead at the break before the game opened up after the interval.

Sean Reidy went over for Ulster but Watson's score and a third penalty from Tonks put them six points clear and they held off a late Ulster storm to claim the win.

Ulster's last five fixtures have all been won by the home side but they made the brighter start at BT Murrayfield.

But Edinburgh, with the inspirational Nasi Manu back firing fit and restored to the starting XV, held firm and it was they that took an early lead after Ulster came in at the side and Tonks kicked the game's first points.

On ten minutes prop Alan Dell - himself a late replacement for Rory Sutherland - went off for head injury assessment but the scrum held firm.

And the backs appeared to be carrying a bit of a threat, Tonks and Tom Brown combined for a break down the right that eventually created a second penalty for Tonks who kicked the hosts into a 6-0 lead.

Ulster were struggling to get a foothold in the game but a superb break by Paul Marshall - the scrum-half celebrating his 150th appearance for Ulster - then so nearly released the clinical Craig Gilroy.

But when the ball was recycled the visitors won a penalty that Nelson dispatched for their first points, Edinburgh 6-3 to the good as the half-hour mark approached.

That was how the game stayed until the interval but in the second half the game opened up a bit and Andrew Trimble and Nick Williams combined to set up the game's first try.

Trimble chipped and regathered and after the ball was recycled through the phases Reidy was able to burrow over from close range, Nelson converting to put them 10-6 ahead.

The hosts needed a response and it was replacement Will Helu who provided it, he got on the outside of his defender, released Damien Hoyland on halfway and seconds later Watson was on the shoulder like any good openside should be to go over.

Nelson's conversion, and a third penalty soon after, stretched the lead to 16-10 but there looked to be a sting in the tail.

Ulster had already turned down a kickable penalty to go for the corner once before in the final ten minutes but once again Alan Solomons' side held firm, Watson at the forefront of a fine defensive showing to keep them riding high in the table.

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