The Suns say it is not a recurrence of the stress injury he incurred last year which kept him out of the side between rounds six and 10.
The AFL releases the 2013 season fixture, every regular season game live on Fox Sports.
The small forward complained of soreness in a different part of the foot last week and because of his previous problems, was sent straight for scans.
Matera said the setback was only expected to cost him two weeks of training, leaving him on track to play at least two NAB Cup games.
"The doc has me wearing a moon boot for the rest of the week as a precaution, and I'll be back training in runners the week after," he said.
"It's a minor setback. I've had a really good pre-season so far so it's not ideal but I'm confident, based on the training I've done, that I'll be available for the NAB Cup."