Oviedo, who has been widely expected to leave the club at some stage this summer, is currently on his summer break after taking part in Costa Rica’s run to the Gold Cup quarter-finals.
As it stands, he is still expected to return next week, though Denver Hume is set to be first choice left back this season as Ross and Sunderland look to the future.
“He won’t return until the 25th of July,” Ross said.
“He was pretty much straight from the play-off off final to join up with Costa Rica [for the Gold Cup].
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“Their involvement in that tournament didn’t finish until June 30th.
“So he’s basically getting the time back that he didn’t get in the summer and then we’ll see where he’s at and take things from there.
“We had a similar situation with him last year, where because of the World Cup he only joined up with us very late.
“It is what it is.
“I don’t think, being the kind of player he is, that he ever really deconditions that much.
“In terms of the work you do on the pitch and bedding things in, he’s obviously missed out on that but it’s just what happens, it was pretty much a month-long involvement in that tournament.”
Oviedo made 39 appearances in all competitions this season but given that he is by some distance the highest earner at the club, the Black Cats will be keen to find a satisfactory resolution to his future this summer.