Waikato left it late before snatching a 21-18 ITM Cup win over Auckland today.

They hit the front 50 seconds after the final siren when hard working wing Dwayne Sweeney scored a try in the left-hand corner at Eden Park in Auckland.

Waikato kept their composure and discipline in the final minutes, their forwards earning field position deep in the Auckland 22 before the ball was flung wide for Sweeney to seal the result.

Steady rain dictated that this would not be a sparkling spectacle but both teams emerged with credit on a day when the wet conditions made ball retention difficult at Eden Park.

Little separated the teams on the scoreboard or the field, with both relying on steadfast defence and robust forward play.

They effectively cancelled each other out until Sweeney's late strike after it appeared Auckland had done enough for victory once No 8 Peter Saili found space to score a try four minutes after halftime on the back of a 30-phase buildup.

That gave Auckland an 18-13 advantage which Waikato first five-eighth Trent Renata reduced to two points with his third penalty of the match midway through the spell.

The scores were tied 13-13 at halftime when the sides went to the break having scored one try each.

The Auckland forwards dominated the breakdown for the opening quarter before Waikato worked their way back into the contest.

Waikato had to wait all of 28 seconds for their first points, courtesy of a Renata penalty after the hosts coughed up possession from the kickoff then infringed at a ruck.

Although Auckland dominated possession for the next 20 minutes the scoring was restricted to penalties traded by first five-eighth Renata and his Auckland opposite Mathew Berquist.

The Waikato defence held firm as they gradually began to contest in all areas and they went ahead in the 24th minute when fullback Sosene Anesi capped a counter-attack launched by Sweeney back on his 22.

Renata's conversion gave Waikato a seven-point buffer but that was erased in the 33rd minute when Auckland flanker Onosa'i Auva'a scored in the left-hand corner after Berquist broke into the 22 then positioned himself for the recycled ball to provide the last pass to Auva'a.