Martinez made nine changes to the Latics side which drew their last Barclays Premier League game at Fulham and they eased past npower League One side Bournemouth 1-0, courtesy of a fantastic strike from Mauro Boselli.
The Cherries put up a valiant effort across both legs, but Martinez was delighted with the performance from the fringe players he brought into his starting line-up.
"The young players and those who needed the minutes showed that they're ready to step up their competition in the squad which is very pleasing to see," he said.
"If you're going to be successful on more than one front then you need quality players competing for their place and that's what we have.
"An outstanding finish from Mauro Boselli was the difference and in the second half, as we expected, Bournemouth came at us a lot more, but we looked a threat on the counter and were unfortunate not to get a second goal."