MELBOURNE, AUSTRALIA - APRIL 13:  Luke Ball of the Magpies grabs his knee after injuring it during the round three AFL match between the Carlton Blues and the Collingwood Magpies at the Melbourne Cricket Ground on April 13, 2012 in Melbourne, Australia.  (Photo by Quinn Rooney/Getty Images)

Luke Ball of the Magpies clutches his knee after injuring it the first time. He will miss the rest of the season. Photo: Getty Images

COLLINGWOOD believes Luke Ball's anterior cruciate ligament tore the second time he wrenched his knee against Carlton on Friday night, as the club defended its decision to send the wounded midfielder back onto the field.

In a devastating blow for Ball and his injury-afflicted club, scans yesterday revealed the respected star onballer had become the third Magpie to fall victim to a knee reconstruction this year.

Ball, 28 next month, is out of contract but has begun discussions with the Magpies for a new deal. He will have traditional reconstructive surgery this week, and has told his management he has no intention of retiring.

''He will play on. He will be back for round one next year,'' his manager, Paul Connors, said.

Collingwood's crisis of fitness and form deepened with Friday night's 10-goal loss to the Blues.

The 2010 premier will not only be without Ball, one of its most influential leaders, for the rest of the season, but has lost All-Australian defender Ben Reid for up to three weeks with a quad strain.

Director of football Geoff Walsh told The Sunday Age the decision to send a strapped-up Ball back into battle in the second quarter, after he twisted his knee in the first, was based on medical clearance and was not influenced by the fact Reid had by then been subbed out of the game.

''The doctor gave clearance to say that he was OK to go back on,'' Walsh said. ''When any player comes off he is assessed by the doctor as to whether he is OK to go back on the ground, and that was the case.''

Later, Walsh told SEN he believed the serious structural damage had been done in the second incident. ''Our doctor has the duty of care of all the players and treats that with the utmost caution, so to go back on [the ground] the first time after an assessment was done in the rooms, that he was given the all-clear, I would think it's logical to assume it [the injury] was the second time.''

Sports physician Peter Larkins said Ball was clearly hampered by a sore knee when he came back on, but had passed a range of tests to suggest he did not have a significant ligament injury.

''The medical staff were quite happy after the first incident that he didn't have an unstable knee; in other words, he didn't have a major ligament injury, and therefore they felt he could run and twist and jump and prove to them that his knee was behaving itself, even though he was sore,'' Larkins said.

''He's had a second incident which tested the knee and the knee failed. My information is that Luke Ball passed those tests and I'm sure he would have been saying, 'I'm right'. There's no doubt he went back on with a sore knee and the question is, did that compromise his next half-hour?''

The loss of Ball was described as devastating by former coach Mick Malthouse, and comes after long-term knee injuries to Brent Macaffer and Andrew Krakouer.

Reid's absence further damages a defensive unit missing the injured Chris Tarrant and departed Leon Davis. Davis' creativity and precise foot skills, in particular, have been missed in the first three rounds, from which the Pies have one win, over Richmond, and losses to the fancied Hawthorn and Carlton.

''He [Ball] is one of my favourites … it's devastating,'' Malthouse said during the coverage of yesterday's Richmond-Melbourne game. ''He's an in-and-under player and a hard player. I don't say it's the end by any stretch of the imagination … but it's devastating. He will get over it, but it's not too good for Collingwood.''

The crisis also follows the much-scrutinised handover from Malthouse to Nathan Buckley. Captain Nick Maxwell was yesterday at a loss to explain the Magpies' lack of intensity around the ball, but was adamant the new coach should not be blamed.

''I wouldn't put it down to the coach at all. 'Bucks' has got a very similar game plan to what Mick had and it's up to the senior players and the leaders of the football club to make sure we do what we need to do,'' he said on SEN.

''Nathan didn't ask us to get smashed in clearances and contested footy and everything else; he asked us to go out and play the way we want to play and we didn't do that.

''I understand that everyone has to analyse it and … see what went wrong and 'why is Collingwood playing the way they have in the first few weeks', but I can guarantee you it's got nothing to do with the coach.''

Among the potential reinforcements, Ben Johnson is nearing the fitness required to return to the senior team and could play against Port Adelaide on Saturday, but Alan Didak and Nathan Brown will need more time in the VFL.