SYDNEY coach John Longmire concedes former Swan Tom Mitchell will be hard to stop in Friday's clash with Hawthorn at the MCG.

Midfielder Mitchell leads the competition in disposals and seems to have gone up another level since being traded to the Hawks late last year.

Mitchell played 65 games in four seasons with Sydney and is only just over 100 touches short of his entire total for last year despite having played nine less games.

Thriving in a side that has slipped from their previously lofty perch, 24-year-old Mitchell is averaging 36 possessions a game and hasn't logged less than 27 in a match this year.

"No matter how hard you work to try and shut him down, it's almost a given he's going to get the ball," Longmire said on Monday.

"He's just so good at finding the footy, so we'll try and reduce his influence on that when he gets the ball.

"But because he's such a good contested ball player that's really really difficult to do.

"Our players know what he can do, but stopping him is another challenge for us."

Longmire would have liked to retain Mitchell, but said equalisation polices like the salary cap made it impossible to hang on to every player.

While Sydney has surged to sixth on the back of 10 wins from its past 11 games, the cagey coach refused to entertain thoughts of a top-four spot.

Although Hawthorn has slipped down the ladder this season, its recent resurgence has Longmire on alert.

"I'm always wary of the Hawks. We've got enormous respect for them, what they've been able to do for a long time let alone this year," Longmire said.

"They've changed their team up. They've beaten Adelaide, they were a kick off beating Geelong, the top two teams, so they are in a real significant form patch at the moment, they beat Fremantle in Perth by nearly 10 goals."

Longmire's respect for the Hawks extends to their coach and his former North Melbourne teammate and good friend Alastair Clarkson.

"I sent him a message last week for his 300th (game in charge of Hawthorn). It's a fantastic achievement what he's been able to do at that footy club," Longmire said.

"I know him really well and you enjoy competing against each other. We've competed against each other as coaches in some of the biggest games."