The eighteen-year-old Norwegian turned down the chance to return to United, where he excelled in a two year spell in their academy, in favour of linking up with the manager that helped him develop in Manchester.
Such a snub may be difficult for some to understand, but the young midfielder would clearly expect more game time in South Wales, while also playing under a manager he was familiar with.
Solskjaer also managed Daehli during his short stay in the Norwegian top flight, where despite making just 15 appearances, the player has confirmed that he is one on Scandinavia's top football prospects, going on to make his international debut for Norway.
This was a fact already known at United, who had let the youngster link up with their former academy boss while including a first option clause as part of the deal. That they were ready to take him back so soon after he left shows how highly he is thought of at Old Trafford, and they wouldn't have envisaged that Solskjaer would head to the Premier League and be able to trump United for the teenager.
Solskjaer told the Daily Star: "I am pleased to announce we have signed Mats from Molde, we had some competition and I'm glad to say he has chosen to come to Cardiff instead of going back to where he was before.
"He had talks with United, they had the option to bring him back as part of the deal with Molde but he has decided to come here and that shows his desire to do well here."
Daehli had been linked to Cardiff as soon as Solskjaer took over, and having played alongside fellow attacking prodigy and new United star Adnan Januzaj in the Red's youth team, the United and Norway legend clearly has high expectations for his new signing.
"Mats is an outstanding talent," Solskjaer said upon completing the deal. "He'll be 19 in March, he's just made his debut for Norway - made two appearances in November - so he'll give us energy and enthusiasm.
"He's got great ball control. I don't want to liken him to many players and put some more pressure on him but... you see now the [Samir] Nasris, the [David] Silvas, that type of player."
With United's ageing midfield struggling at times this season, the fact that Januzaj could have been playing alongside Paul Pogba, Ravel Morrison and Daehli in a quartet full of promise will surely sadden their fans, and begs the question - how did these players slip the net?
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