CARLTON will continue to play it safe with important ruckman Matthew Kreuzer as he recovers from a raised heartbeat.

Kreuzer will miss his second successive game when Carlton takes on Gold Coast this weekend, and he is now a week-by-week proposition for the Blues.

The ruckman left the field early during his side's clash with St Kilda a fortnight ago due to a shortness of breath and an elevated heart rate.

MATCH PREVIEW Suns v Blues

Brendon Bolton said last week that he expected Kreuzer to only miss one match, but the coach revealed on Friday that specialists wanted to do further testing on the 29-year-old.

Kreuzer returned to full training almost immediately after the incident, but the Blues will understandably continue to put the safety of the 200cm ruckman first and will persist with Matthew Lobbe against the Suns.

"The specialists have said that they still want to do some further testing," Bolton said.

"I think everything is OK, but given that there's not been a great deal of continuity for him over the last few weeks, we've got to continue to build him up again.

"There will be some ongoing testing there."

Maligned forward Levi Casboult will return to the VFL this weekend, having managed just five disposals in his one game back with the senior team last week.

It means youngster Harry McKay will share the ruck duties with Lobbe at Metricon Stadium.

"To be fair to Levi, he's had – like many of our players – not a great deal of continuity," Bolton said.

"He had the broken ribs, then he had that dislocated finger. His form, as a result of that, has been inconsistent.

"Levi is really determined to get back on track, so this week the challenge for him is to deliver in the VFL."