The 25-year old former Leeds United and Columbus Crew winger retired from the game time in February after stating publicly that he is gay but he is back in training, this time with the Galaxy, with the view of perhaps joining the club down the track.
Arena was very supportive of Rogers, saying: "He looked a lot sharper than I thought he would today. Given the fact he's been away from the game for a while."
He added: "I think our league is a progressive league. Our league is a league comprised of all different races, colors and creeds, and to be accepting of a gay athlete I don't think is anything that's difficult for our league.
"We've had a great mentality of being open and tolerant of all different kinds of people, views, what have you. We've known Robbie a bunch of years and he's a first-class person and we're only too excited to have him here with us."