Melbourne Heart stand-in skipper Matt Thompson says the club can't afford any more major slip-ups if they are to break back into the top six and cement a spot in the A-League finals.After Saturday's away clash with Perth, the seventh-placed Heart take on top-six sides Gold Coast, Melbourne Victory, Brisbane Roar and Central Coast before rounding out the regular season against unpredictable defending champions Sydney.Thompson, who will captain the side against Glory in place of injured skipper Simon Colosimo, said the Heart wanted to keep its destiny in its own hands rather than relying on other teams to fall in a heap.The Heart, who went seven games without a victory before their current three-game winning streak, sit one point adrift of sixth-placed Newcastle, and two points shy of arch rivals Melbourne Victory."We know what we've got to do," Thompson said in relation to Heart's finals hopes."If we do slip up it's one of those ones where we hope those other teams around us slip us as well."But the idea is to win all the games and we shouldn't have anything to worry about."We mentioned a couple of weeks ago that every game is a grand final and it's a cliche but it's a bit like that at the moment."We know that we're in a situation that if we do stuff up it's going to make it a lot harder because Newcastle still have a game in hand and Victory are still in front."With any luck after a couple of wins, we could find ourselves cemented in that top six and maybe focus on something a bit higher."If we can win five or six of the next six then we should be sweet to get into those finals."A win in Perth would do wonders for Heart's finals hopes but Thompson conceded it wouldn't be an easy task against a Glory outfit that has shown far greater fight in the past five weeks."Perth can be sitting last on the table or first, you always know what you're going to get when you come to Perth," Thompson said."For some reason they're a completely different side when they play in Perth."Thompson said Michael Beauchamp would more than cover for the absence of Colosimo, who is struggling with a calf complaint.The Glory were dealt a major blow earlier this week when defender Chris Coyne, who missed the first 22 games of the season due to a transfer oversight, was ruled out of the rest of the campaign due to a torn Achilles tendon.