Collingwood coach Nathan Buckley delivered an old-fashioned spray to Jarrod Witts during Saturday’s 29-point loss to Hawthorn, challenging the project ruckman to stand tall and believe in himself.

Buckley later took to Twitter to express his regret at the incident, saying he was “too overt”.

The Hawks broke the game open late in the third quarter with three goals in as many minutes, with Buckley furious at Witts’ efforts at the centre bounces during that crucial period.

The coach made his feelings known to Witts when the 209cm ruckman headed to the bench, yelling at him loudly and grabbing his jumper.

“I’ve got great belief in what he’s going to be capable of achieving and I don’t think he shares that belief at the moment,” said Buckley .

“It was designed as a prickle, it was designed to really challenge him and wake him up in some ways.

“We’re getting about 85 per cent of what he’s capable of right now and there’s gold in that last 15 per cent.”

Witts did respond to the challenge with an improved performance in the last quarter.

“He kicked a couple of goals and took a contested mark in the goalsquare but we want our big fellas to play like big fellas,” said Buckley.

“We want them to play big and tall and tough and have blokes stand up taller around them.

“And I didn’t think Wittsy was doing that for most of the game and definitely not in that five or 10 minute period leading up to three-quarter time.”

Witts grew up in Sydney and attracted the attention of the Magpies, who drafted him under the scholarship system in 2011.

The 21-year-old was playing his 18th AFL match on Saturday.

Buckley later tweeted that he had gone overboard in his spray at Witts.

Incident with Wittsy says more about his coach than the player. Still room for challenges to be laid in this game but too overt today.

— Nathan Buckley (@ncb_cfc) June 21, 2014