HAWTHORN utility Brendan Whitecross has undergone his second knee reconstruction, this time using the patella tendon from his other knee.

The luckless 23-year-old ruptured his right anterior cruciate ligament for the second time when he attempted to tackle in the frantic dying stages of Friday night's preliminary final win over Geelong.

He sustained the same injury nearly 12 months ago in the Hawks' qualifying final against Collingwood.

Whitecross had a traditional reconstruction at the time, using his hamstring tendon to repair the damaged ligament.

This time, he has again opted to not utilise the LARS (artificial ligament) technology and instead has had the operation using the patella tendon from his opposite knee.

Leading medico Dr Peter Larkins said the operation had taken the usual path of using the knee tendon for a second rupture. 

"He was always going to get it done reasonably quickly," Larkins said.

"Certainly when you're having a second one, you'll go for the opposite to what you had the first time.

"He's already had a hamstring so this was a patella tendon being used, which is the other version of the hamstring option.

"When you've already had a hamstring, you've either got to take it from the other knee and rob your good knee of its hamstring or you just take the patella tendon, which has got a good track record."

St Kilda veteran Lenny Hayes, Carlton ruckman Matthew Kreuzer, Collingwood backman Nathan Brown and newly-retired Essendon ruckman David Hille have previously had knee reconstructions using the patella tendon.

Larkins said both were popular in Australia and came with positives and negatives.

"You don't have the potential risks of the hamstrings giving trouble afterwards [with patella tendon use]," Larkins said.

"But, it has an additional difference in that you sometimes get some soreness over the front of the knee when you kneel down or get a knock on the knee."

Whitecross returned to senior football in round 14 this season after his last reconstruction.

While he faces a similar timeframe for recovery, Larkins said patella tendon operations could sometimes progress slightly faster.

"There's no trauma to the hamstrings, they only take out part of the patella tendon so you've still got a patella tendon there," he said.

"Overall, the graft inside the knee still takes 12 to 18 months to get fully matured, irrespective of which graft you put in.

"In terms of what you can do in the first three months, the patella tendon patients tend to get their muscles back at bit quicker because they're doing a bit more knee exercise compared to the hamstring one."

Having been through the lengthy rehabilitation process, Whitecross can expect the biggest hurdle to be the psychological aspect.

Larkins believes 10 months is the earliest return the young Hawk should aim for, leaving him with a projected window of late June or early July.

"There's an advantage because he's been through it before so he knows the routine. He knows the timing and when you run and when you do sprints and he'll be familiar with the pattern on how you rehabilitate it," he said.

"The negative will be that there's a bit more of a psychological concern because he did everything right last time

"The thought of 'Do I need to do anything different?' will be at the back of his mind but generally it will be the same process. There's no extra tricks."