Elrich beat Ferreira by a lot: Gombau
The Mariners shook the error-prone home side early with a disciplined high press and struck the first blow when Anthony Caceres blazed from long range in the 23rd minute.
Just when it looked like United's form drought would extend to one win from their past six, Marcelo Carrusca equalised just a minute later and Gombau's charges never looked back, stealing the lead through Craig Goodwin in the 67th.
“After we lost two games (in a row), we didn't have the confidence in ourselves," Gombau said.
"The first 20 minutes we didn't have the passing lines and the style we play.
"For me the key moment was when they scored, and one minute later we scored.
"This made the team trust in itself and try to play our football.
"After the players started to get their confidence, we started to play our style of football again and we did that in the second half."
It wasn't the most memorable or sparking victory in Adelaide's history but it was enough for the Reds to grab a share of second spot with Wellington Phoenix.
Gombau actually felt Adelaide played better football in last week's 2-0 away loss to Phoenix.
"Sometimes when you haven't been getting the results, you don't have this confidence in what you are doing," Gombau said.
"Normally you see the football (aligned) with the results.
"For me, we did very well in Wellington and didn't get the result.
"Today we maybe didn't play as good and we got the result."
Aside from the Reds' dusty form, most of the pre-match hype centred around the reneging of the so-called 'gentleman's agreement' that in-form Mariners winger Fabio Ferreira wouldn't play against his old side.
Unflurried, Gombau simply set his best all-round stopper, Tarek Elrich, onto Ferreira and the result was a handsome win for new Socceroo Elrich.
"Elrich beat Ferreira, by a lot," Gombau said.
"Elrich was one of the best players on the field.
"Every single game he's one of the two to three best players in his performance.
"He deserves what is coming from the Socceroos."
Conversely, young striker Awer Mabil will miss the next few weeks after sustaining a quad injury during the week.
"Awer had a scan and the doctor saw he has a problem in his quad and he needs to be out for two to three weeks," Gombau said.
"This is bad news for us. He missed training two days before the game.
"Every single team has injuries and we need to deal with this."