Mercedes started dating Browning (Joe Thompson) to make Riley Costello jealous earlier this year, but the pair ended up developing a stronger connection than they had anticipated.
Browning is expected to make another appearance on the soap in the coming weeks, and Metcalfe told Inside Soap's Yearbook 2013 that she would be pleased to see him back.
Metcalfe explained: "For three years the scriptwriters tried to tell me Malachy Fisher was Mercedes's soul mate, and then they tried to tell me that Riley was. But I told them no, it's got to be Doctor Browning.
"He gives as good as he gets and I think that's really good for my character, especially when Mercedes has been involved with so many men in the village."
Mercedes is currently in a psychiatric unit after her attempt to frame Mitzeee Minniver for attempted murder was exposed. Upcoming episodes will see her face trial for her recent crimes.
Asked whether Mercedes can be redeemed, Metcalfe replied: "I'm not sure if I can give too much away. All I can say is there's a really big storyline coming up - and I think the audience will be shocked by it."
Hollyoaks airs weeknights at 6.30pm on Channel 4, with first look screenings at 7pm on E4.