Adelaide United all but nailed down their playoffs berth with a disciplined 1-0 win over Wellington Phoenix at Westpac Stadium.

Adelaide hadn’t won in Wellington since 2007, and had to work hard for the win on Sunday, with only Marcelo Carrusca’s second-half penalty separating the two teams after 90 minutes.

The win lifts them into second place on the ladder with 40 points, one point clear of third-placed Central Coast Mariners with Western Sydney fourth on 38.

A scoreless first half wasn’t without incident, with both teams delivering some crunching tackles in a torrid midfield battle.

The Phoenix took time to build momentum, but finished strongly, Kenny Cunningham and Matthew Ridenton working hard to create space and sending through some tantalising chances for Stein Huysegems and Jeremy Brockie up front.

The Belgian had the best chance of the opening spell right on the halftime whistle, one-on-one with Adelaide’s Eugene Galekovic, only for the sprawling keeper to tip the shot wide.

Wellington lifted their intensity after the restart, but Adelaide’s control in the midfield began to tell, and paid dividends in the 57th minute when Tarek Elrich was sliced down in the box by Phoenix skipper Andrew Durante.

Carrusca stepped up to convert the penalty and, with a goal under their belts, Adelaide looked increasingly dangerous in working the ball around.

Not even the introduction of Costa Rican playmaker Carlos Hernandez, back from a calf injury, could lift the Phoenix and the match became increasingly fractious, with eight yellow cards testament to its intensity.

Wellington remain mired at the wrong end of the ladder in eighth place, with just seven wins from 25 matches.