Adelaide edged closer to an A-League home final after drawing 0-0 with Melbourne City in an absorbing contest at AAMI Park.
Adelaide sit fourth on the ladder with the result, while City stay in sixth, trailing next round's opponent Wellington on goal difference. City had the better of the second half but were unable to break the deadlock, while their goalkeeper Eugene Galekovic pulled off a string of saves throughout the match to secure a crucial point.
His opposite, Paul Izzo, also earned his keep with some superb stops, with 36 total shots which was the second most in a goalless draw in the past seven seasons.
City coach Warren Joyce said United dominated the first half but felt his side deserved the win after their second half showing.
"We had a couple of chances in the first half but I thought they were the better side in the first half and I thought we were the better side in the second," Joyce said. "Our passing was much better and we had some good opportunities to score and their chances were restricted to counters or set plays. I thought we deserved to win."
Both teams arrived ready to play, firing shots within the opening two minutes. Galekovic saved a Craig Goodwin shot into the left corner before a Kearyn Baccus curling strike from outside the box hit the post, much to the relief of United's keeper Paul Izzo.
Looking for a record 11 games without a loss at home, City found their rhythm first and started to build some pressure on the visitors. United's Dutch striker Jordy Thomassen went down at the 31-minute mark with a rolled ankle and was replaced. His coach Marco Kurz said postmatch it wasn't clear how serious the injury was.
The change in personnel sparked the Reds' attack, with substitute Nikola Mileusnic hitting the right post in his first minute on the pitch.
Soon after, Galekovic again proved his worth with a double save -- first stopping a blast by George Blackwood before securing a Ben Halloran shot to keep the the match scoreless at the break.
The tide turned again early in the second half with momentum back with City. Their first big chance of the half came in the 63rd minute through Harrison Delbridge, with Izzo earning his keep by tipping his header from a set piece onto the bar.
The home side continued to dominate the second stanza with Jamie Maclaren looking for a matchwinner when he beat Izzo for pace but his strike struck the left post.
United also had a late chance with a Goodwin free-kick in the 87th minute but Galekovic again saved the day.