Nel try helps Stormers to first place in Super Rugby

The outside centre, who notched a post-hooter winning try against the Golden Lions last Saturday, struck on 53 minutes in Cape Town to give the home side a 15-point advantage.

Nel sold a dummy and scored after pressure from the South Africans created a gap in the Argentines' defence at a wet and murky Newlands stadium.

Fly-half Damian Willemse converted for a 17-0 lead that gave the hosts breathing space ahead of a comeback by the visitors which yielded a try from number eight Rodrigo Bruni.

Jaguares fly-half Domingo Miotti converted and the Buenos Aires outfit thought they had scored again when wing Sebastian Cancelliere went over only for the try to be disallowed.

The sixth-placed South Americans finished strongly but could not score the try or penalty that would have secured a losing bonus point.

Scrum-half Herschel Jantjies scored the other try for the winners after an interception and Willemse kicked a penalty and two conversions for the Stormers, who led 3-0 at half-time.

After conceding three early scrum penalties, the Jaguares replaced tighthead prop Santiago Medrano with Joel Sclavi on 29 minutes.

Sclavi stabilised the scrum, taking away the only obvious advantage either side enjoyed in a dour tussle. 

The Stormers are the only side with a perfect record after four rounds having beaten the Wellington Hurricanes, Northern Bulls and Lions previously.

They have 17 points to lead defending champions the Canterbury Crusaders by three and the ACT Brumbies by four.

Stormers' Jamie Roberts, the Wales and British and Irish Lions centre, was voted man of the match and said his new team have reached "about 60 percent of their potential".

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"We are building and improving and did well to win this evening against a very good Jaguares team that had a defence that was very difficult to penetrate," he said.

"Our forwards put in a massive shift and it was wonderful to see the pride with which we defended in the closing stages."