Middlesbrough are due to face QPR at Loftus Road on Friday evening, and Friend is under no illusions as to how tough a test his side face.
Hasselbaink was appointed back in December, and he made a slow start at the London club.
Rangers’ form in the initial weeks after the Dutch boss arrived was poor, but they have shown signs of great encouragement more recently.
QPR have lost just one of their last seven matches, and Boro defender Friend admits that he has noted the improvement that Rangers have made.
“QPR have picked up recently,” he said. “Jimmy Floyd Hasselbaink had a tough start but he’s a good manager and they’ve bought into his way.
“They’re starting to get results.”
QPR have built their success around the strength of their home form, with Rangers winning their last three matches in front of their own fans.
QPR have easily dispatched with Birmingham City, Derby County and Brentford recently, but Friend believes that the pitch at Loftus Road could suit his side.
“It’s quite a tight pitch to go to and I think it will suit us to get on top of them there and the pressure is on them because they’re at home,” the Boro defender added.
“We can go and win there for sure and it’s a Friday night on TV so it’s a good one for us.”
QPR are currently in 11th place in the Championship table, while Middlesbrough occupy third spot and would move into the automatic promotion spaces if they are able to win on Friday.