When Middlesbrough signed Lewis O'Brien in the summer of 2023, Michael Carrick said he'd sought the advice of good friend and former Manchester United team-mate Wayne Rooney.

Rooney had managed O'Brien and DC United before his loan switch to Boro and he gave the signing his stamp of approval when Carrick picked up the phone. Having managed Morgan Whittaker for the majority of this season, it would be no surprise if the Boro boss sought Rooney's thoughts once again.

Whittaker joined Boro on Friday evening from Plymouth Argyle, signing a four-and-a-half-year deal at the Riverside. If Carrick did pick up the phone to his Man Utd team-mate again, Rooney's previous comments on the forward - who he managed at both Derby County and Plymouth - likely suggest he'd have once again given Carrick the green light.

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Speaking earlier this season about Whittaker, and offering insight into his ability and versatility, Rooney said: "In quite a few games this season, in possession, Morgan has played in the number 10 role. You always want your best players in the best positions on the pitch to try to score goals. We have tried different things with Morgan.

"Sometimes you have to look at the opposition as well and how they set up. If we feel it's right for Morgan to play inside we will do that. If it's right for him to play out wide, or play on the left, we will look at different options. He has scored some big goals for us late on and, of course, I'm sure if you ask him he will want to score more goals.

"He's a goalscorer, he's a player who has really big moments for us and the one thing I would never take away from him is his ability to come inside and shoot because he has got a fantastic left foot. When he gets it right, he runs away and celebrates. When he doesn't get it right then you can look at it and say he hasn't scored, but I think we don't shoot enough. I have said this to the players."

Whittaker was a product of the Derby County academy. Rooney was the Derby head coach that sold him to Swansea City in February 2021, though after reuniting with him at Plymouth, the Manchester United legend insisted it wasn't really by choice.

In an interview with talkSport when asked how good Whittaker was, he said: "I sold him! No, Morgan is a fantastic lad. [Derby] were in administration, so we had no option but to sell him and he went to Swansea. The one thing I said to Morgan at the time was, on the ball he's fantastic, he scores some fantastic goals.

"The next step now is his overall game, this season that's something we've really worked on and he's been fantastic. His work rate, his effort to get back and help the team out alongside his quality he brings with his match winner, he's such an important player for us. The reason I leave him on the pitch every game is because he has moments, like you could see on Saturday, he has those moments, 97th minute and he wins us the game."

It's been a difficult season for Whittaker, and Plymouth overall, this term. The new Boro man has only four goals this season - though his final goal for the Green Army was a memorable strike against Brentford in an FA Cup victory. Last season though, the 24-year-old enjoyed a remarkable campaign, scoring 20 goals and registering eight assists.

Steven Schumacher was his manager for the majority of his time at Home Park, and it's fair to say the former Stoke City boss was also a big fan of Boro's second January signing. He also highlighted a key area for improvement that Rooney also mentioned.

Schumacher said: "He's an incredibly talented player. That's what we brought him here for, to score and create goals, and that's what he's doing. I think there were a few really good talented players out there today and Morgan has shown he is one of the best players in the Championship.

""He has got loads of quality and it's there for everyone to see. They all know what he's good at and where he needs to improve is some of his off-the-ball work, which I think he's getting better at. He's getting a better grasp of where he needs to be positionally, and that's something I need to work with him all the time on.

"I keep reminding him not to forget to do those roles because when he does do it it gives our team an opportunity to get the ball back quicker, and then get the ball to him, which gives us a chance to score goals. So that's what he has got to do, he has got to do both sides of the game and I think he's doing brilliantly."