Reds boss Brendan Rodgers has suggested Downing's long-term position could be at fullback.
"It's a good thing because before (Downing played left-back) there was just myself and Jack Robinson," Enrique told liverpoolfc.com. "With the way we intend to play, that is with the right-back and left-back attacking, Stewart can fit in well.
"He's a good lad and I'm happy for him. We have many, many games this year and so it's good to have competition for places."