MELBOURNE will aggressively set its sights on targeting an A-grade midfielder as it looks to push into the same league as the competition's top-eight teams, coach Paul Roos says.

The Demons' bookends are developing nicely, with Jesse Hogan set to command the forward line for the next 10 years and Tom McDonald to do the same patrolling the back half.

But Roos sees one main gap in Melbourne's list, and that is a premium player to add to its developing stock of onballers.

"If you look at the really good teams it's the versatility through their midfield area," Roos said on Sunday.

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"We can't have enough good players full stop – I'm happy to get a tall and a midfielder.

"To take the next step, we'll evolve naturally as a group, but it would still be great to add an A+ midfielder."

Both Hogan and McDonald, who started the first half inside forward 50 in the Demons' 24-point win over the Brisbane Lions on Sunday, were key contributors in their side's victory.

Hogan was the difference between the sides – booting four goals and hauling in 11 marks, which included the defining mark and goal to put an end to the Lions' challenge late in the final term.

"The [mark and goal] in the last quarter was really important – it gave our blokes a little bit of lift when he put the ball through," Roos said of Hogan.

"He's had a really good day."

Hogan's was Melbourne's only goal for the second half after a distinct drop off after the major break – the Demons led by 38 points at half-time – allowed the Lions back into the contest.

As much as Roos was disappointed by his side's inability to finish the game off, he said if the Demons were faced with a similar challenge in the last few years they might have let the match slip.

Roos put the turnaround in the game down to Melbourne's inability to consistently hit targets when moving the ball forward.

"It was more our ball use. In the second half we had a lot of opportunities. Probably those concentration errors, I call them, with the players, the ones where we're out in open space and turn the ball over (cost us)," Roos said.

"They (the Lions) were always going to up the ante in the second half … we just couldn't keep the scoreboard ticking over – we were kicking points again – which doesn't help."

But Roos was delighted that Melbourne notched its fifth victory of the season, one more than it achieved in 2014 with seven games remaining.

"I don't think we can undervalue that. There's no question that for us to go to members and sponsors and say that we're improving you need to see improvement," Roos said.

"We felt we'd had a really good five-week patch of footy but up until today we'd won one game, so 2-3 is a lot better than 1-4.

"It shows the fans that we are improving and they can see some improvement in individual players.

"It was a really important win for us, there's no doubt about that."