After an impressive debut 2011, his second season was really a bad case of 'second year blues' for the former Victorian.
O'Shea played the first three games of the year, but found himself back in the SANFL after round three of the AFL season.
Playing for South Adelaide where he would slowly rebuild towards an AFL return, he was called into the team against Geelong in round fourteen.
But things went pear shaped for him after that match, when stress fractures in his foot forced him to miss the rest of the year following surgery.
Fully recovered and after a good pre-season where he maintained his status as one of the club's fittest players, O'Shea is focussed on making up for a lost year.
"It was good to have a run around and be back playing footy," O'Shea told portadelaidefc.com.au.
"The first [NAB Cup] game was really good for us as a team and showed we were really competetive even though we dropped away a bit in the second [game].
"[In the] first game we really hit our benchmarks and it was good to get a win.
O'Shea ran through the midfield in both games and in each was reasonably effective - with the third most disposals in the opening game and as one of only four goal kickers in the second.
He says the team will need to put the loss against the Crows behind them and turn their focus to an improved showing against Melbourne in Renmark on March 3.
"It was good to have a run through the midfield with guys like Boaky and Brad in there its good to have them giving you the ball and for me to do the same in return."
"We knew the second game would be tougher [and] now we just need to focus on getting right for Renmark in a couple of weeks time."
Port Adelaide takes on Melbourne in the second round of the NAB Cup at Renmark Oval on March 3.
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