The pair have put pen to paper on deals that will see them join the Hyundai A-League 2011 Grand Finalists for next season, plus the group stage of the AFC Champions League 2012. Pellegrino has also committed to the club for the Hyundai A-League 2012/13 season.
"We're delighted to bring in players with the qualities of Adriano and Brad to our club," said Mariners Chairman Peter Turnbull.
"The club is coming off an excellent season with another Grand Final appearance, and we're fortunate to have our second AFC Champions League campaign to look forward to in the near future as well.
"Bolstering our squad with the addition of these two established but youthful players sees us move into this exciting time with momentum and with plenty for everyone on the Central Coast to embrace."