Second half goals from Carlos Hernandez and Matthew Kemp plus an own goal from Nigel Boogard handed a 3-0  win to Victory and kept the visitors at the top of the A-League ladder.

But McKinna admitted he was shocked by the final scoreline, almost an exact reversal of the Mariners' 4-0 win over Melbourne at Etihad Stadium in round 14.

"Tonight it wasn't to be. We got beaten 3-0, but we can't believe it," he said. "They were clinical in that front third, we weren't as clinical as them.

"It was probably similar to the Melbourne game down there when we defended well and scored four goals. The first 20 minutes was good defensively, we got into the game and then 20 minutes before half time we got on top.

"After half time we were on top again, and then Matthew Lewis, who had a good game, let Kemp get in behind him, it was a great delivery and a good finish by a quality player.

"The second goal was another great cross for Kempy to finish into the roof of the net, and that was it, game gone. "

McKinna was left to rue the opportunities squandered by his side.

"At 1-0, Pedj (Bojic) hit the post, and that could have turned the game," he said. "Up until they scored I don't think Danny (Vukovic) had a save to make.

"Before they scored, they didn't really look like scoring, we looked quite comfortable with them."

The Mariners are still fourth, and can stay there depending on the outcome of Newcastle Jets' clash with Gold Coast United, but McKinna is still confident of a top two finish.

He added: "It's always achievable, but it's going to be hard. With the results this season, anyone who gets into the top six is going to be in with a shout because everybody has been taking points off everybody.

"It is a long way but we have to believe that we can get in there."