8:41AM BST 07 Jul 2011
Brown has been joined on Wearside this morning by O'Shea, who is having a medical, before travelling to the training ground to meet his new teammates.
A successful completion of both deals would take manager Steve Bruce's summer signings to date to eight.
The Republic of Ireland international is thought to have spent the night in a hotel in the north east, following Brown up from Manchester after the England international met his new colleagues yesterday.
Sunderland are expected to pay around £8m for the pair having had a £12m combined offer for Brown, O'Shea and Darron Gibson accepted last month.
Sunderland boss Steve Bruce still hopes to complete the signing of midfielder Gibson, although the Irishman, who has also been linked with Newcastle United, will have to lower his wage demands significantly.