Both Adelaide United and Melbourne City booked their places in the A-League semi-finals with wins over Brisbane Roar and Wellington Phoenix respectively, in two very different games. Adelaide and Brisbane’s approaches led to an open affair while Wellington and City looked to nullify the opposition’s strong points – but allow us first to readdress points raised just weeks ago in this column.

Elimination final 1: Adelaide United v Brisbane Roar

It was only last week that Richard Parkin highlighted Adelaide’s new use of a 3-4-3 which helped defeat Melbourne City. Having earlier used the system, it was Isaias who played a dual role, acting as a fourth midfielder when Adelaide had the ball and then dropping back into central defence when possession was lost. This system, designed to create overloads in the middle of the park, also allowed extra freedom to playmaker Marcelo Carrusca. Last week, even though Adelaide was without both Carrusca and Isaias, Josep Gombau still opted to line his side up in a 3-4-3 and instead used Sergio Cirio in a role on the left side of midfield.

The system worked well for Adelaide but with Carrusca and Isaias returning to the side for the game against Brisbane, the logical assumption would have been for both players to resume their roles used when previously playing a 3-4-3.

Instead, Osama Malik was entrusted to continue in the dual role at the base of midfield, with Isaias slotting in on the left side of the diamond and, somewhat surprisingly, Carrusca playing on the right of midfield. This set up, when coupled with the fact Brisbane Roar looked to press, led to an exciting and open game.

When Adelaide were in possession, Roar’s front three were able to press man-for-man against Adelaide’s three centre-backs while Devante Clut moved onto Malik at the base of midfield. It was then Luke Brattan and Matt McKay’s responsibility to apply pressure on the outside midfielders Isaias and Carrusca.

But life was made difficult for Brisbane in midfield. This was because Gombau instructed his two outside midfielders to take up wider positions, forcing either Brattan or McKay out of the centre in order to close them down. Then, with another midfielder in Jimmy Jeggo, the Reds, once they had possession in midfield, were able to use their numerical advantage.

With Jeggo’s advanced role in midfield, and with McKay and Brattan preoccupied with Isaias and Carrusca, it became the responsibility of a Brisbane centre-back to step forward and this led to Adelaide’s first goal when James Donachie needlessly went through the back of Jeggo as he received the ball in midfield before Craig Goodwin executed a spectacular free-kick.

But the desire to create overloads in midfield left Adelaide with a 3-on-3 at the back and Thomas Broich’s equaliser came as a direct result of this – with Brisbane pressing and forcing a turnover high up the pitch before taking advantage of the high-risk Adelaide approach.

Elimination final 2: Wellington Phoenix v Melbourne City

The second of the weekend’s games, between the Phoenix and City, wasn’t nearly as open as the first but it still addressed similar themes to ones raised here a few weeks ago.

Then, Melbourne City’s use of the 4-4-2 diamond was analysed as they looked to prevent Wellington from creating overloads in the centre of midfield. The approach there led to an open encounter but after City struggled to utilise the system against Adelaide in round 27, coach John van ’t Schip instead looked to close down the game in midfield when they travelled to New Zealand.

In order to do that, City switched to a 4-2-3-1 with Aaron Mooy and Erik Paartalu as deeper midfielders behind Robi Koren. In order to prevent Wellington from playing through midfield, City’s wingers David Williams and Harry Novillo would take up narrow defensive positions to clog up the middle of the park.

This frustrated Phoenix, with coach Ernie Merrick saying after the game his side found it difficult to play how they would have liked.

“I felt it was a very difficult game to go out on, I don’t think we showed what we can do at all,” he said. “To Melbourne City’s credit they put us under a lot of pressure and they closed down our midfield. Melbourne City came here with the right attitude, they competed all over the park, they pressed us and they stopped our midfield.”

By taking up narrow defensive positions, City not only clogged up the midfield but they also presented themselves with counter attacking opportunities. This was evident early in the match when, with Michael McGlinchey taking up a wide position high on the left, Manny Muscat looked to underlap to exploit the space between Paulo Retre and Connor Chapman. But once possession was lost, Williams would burst in behind Muscat to exploit the spaces in behind the Wellington fullback.

To address this, Merrick quickly switched Vince Lia and Louis Fenton, with Fenton moving out to the left side of the diamond. This allowed Muscat to take up more conservative positions, preventing the counter attacking outlet for City, while Fenton instead made runs in behind when McGlinchey received wide on the left.