WINGED Carlton skipper Marc Murphy was among a group of big-name onlookers as the Blues gritted their way through a tough two-hour training session on Wednesday. 

Murphy, who had a follow-up operation on his reconstructed left shoulder last month, only completed stationary skill work away from the main group for 20 minutes before heading indoors at Ikon Park.

Although the midfielder was on restricted duties, he didn't appear to be in discomfort after previously complaining of pain in his shoulder and the 28-year-old is expected to resume full training within the next month.

Levi Casboult also didn't take part in the main session as he manages a knee complaint from last season, with the spearhead only completing some ball-handling drills and taking a handful of shots at goal.

Murphy and Casboult were joined by injury-plagued ruckman Matthew Kreuzer and veteran Andrew Walker in a small group on modified programs, while their teammates were put through their paces in a searching session. 

Accused of being an introverted team, the Blues were noticeably vocal as they hit the track for the open session in front of several hundred supporters – with rookie coach Brendon Bolton also loudly barking demands for intensity in match simulation drills.

The willing session claimed one casualty when running defender Dylan Buckley hurt his left ankle after being wrapped up in a heavy tackle. 

Buckley was helped from the field but managed to walk unaided into the clubrooms and the injury didn't appear too serious, although he didn't rejoin training.

With many of Carlton's other leaders on the sidelines, 2014 club champion Bryce Gibbs was demanding and encouraging of his teammates as he looks to put an indifferent, injury-shortened season behind him. 

The Blues put an emphasis on defensive structures, positioning and sweeping the ball from defence on Wednesday, with Bolton's desire to create a learning environment clear to see.

The rookie coach and his assistants regularly called the players in for instruction and Bolton took a particular interest in overseeing Patrick Cripps' running technique away from the main squad. 

Father-son draft pick Jack Silvagni was a favourite among fans, while No.1 draft pick Jacob Weitering also looked right at home in navy blue. 

Weitering showed his strength in one-on-one duels with some of his fellow draftees and appears primed for his club debut in the opening NAB Challenge clash against Hawthorn in Launceston on February 18.