Jose Mourinho praised Henrikh Mkhitaryan's determination to impress, improve and influence after his fine solo goal helped Manchester United's progress to the Europa League knockout stages.
The 27-year-old's struggles to make the squad, never mind the starting line-up, puzzled onlookers after arriving from Borussia Dortmund to much fanfare.
Mourinho explained that Mkhitaryan was still getting used to the rigours of English football, but his frustration with the player was clear when saying last month that the Armenian had to "do more".
The attacking midfielder seems to have heeded that advice, appearing in a fifth successive United match and scoring a fine solo goal to open the scoring at Zorya Luhansk.
Mkhitaryan's goal early in the first half was complemented by a late Zlatan Ibrahimovic strike in Ukraine, wrapping up a 2-0 win that saw Mourinho's men progress from Group A as runners-up.
''He has a strong mentality,'' Mourinho said. ''He was very determined to fight against his difficult adaptation, and he's doing that in the best way.
''He worked really hard physically, tactically and the talent we know is there. The talent we knew what we were buying.
''He fought to improve tactically, he fought to improve physically, and now he is playing good in the Premier League, good in the Europa League and the EFL Cup, and now evolving a bit more happiness for him, so I'm very pleased.''
That satisfaction also goes for his side's display in difficult conditions in Odessa, securing a place in Monday's last-32 draw having emerged unscathed on a poor pitch.