Manchester City have sent the 20-year-old attacking midfielder out on loan to Portsmouth to experience regular first-team football.
Robertson has established himself as a regular in the squad and has featured in nine games in the league so far, starting six of them.
Clarke stated that the Manchester City loanee is a technically brilliant player and pointed out that Colby Bishop and Robertson are working very nicely in Portsmouth’s attacking third.
“I just want to see a little bit more from him”, Clarke said on the What The EFL Podcast.
“He is getting rave reviews.
“He is on loan from Manchester City, 20-year-old.
“Playing in behind Colby Bishop in 4-2-3-1 and they are working very, very nicely.
“He looks technically an excellent player at League One level.”
Robertson has picked up two assists in Pompey’s last two league games and the Manchester City loanee will be eager to continue his impressive performances when his side take on Wycombe Wanderers tonight.