Royle sprung a surprise by handing the veteran stopper a recall but he felt it was necessary to have a more vocal presence between the posts.
He told the Oldham Advertiser: "I wanted to get someone else to talk in the team.
"If Sean Gregan doesn't communicate then we haven't got anyone else who opens their mouth.
"He's a good organiser and I couldn't actually fault him with any of the three goals."
Royle also explained his reason for substituting Stefan Stam after just 39 minutes at the Withdean Stadium, adding: "I did Stefan Stam a favour by taking him off, he was nowhere near it."
Source: Team_Talk