Moriba has been getting more game time with the Barcelona first team of late, and Koeman is glad with what he's seen so far from the 18-year-old.
"He's one of the young players we have," the Dutchman noted.
"He's played with Barcelona B, with the first team... he's done very well and he's the competition we have in midfield.
"He can contribute a lot, like Riqui [Puig]. There are several young players who are knocking on the door [of the starting line-up]."