The Manchester United midfielder’s popularity has risen in the second half of the season after a string of influential performances for the Red Devils.
Fellaini is expected to line up for the 20-time English champions against Arsenal at Old Trafford in the Premier League on Sunday afternoon.
And the towering Red Devils midfielder uploaded a snap from his afternoon at the New Balance studios ahead of the visit of the Gunners.
Fellaini wrote: “Great day with @NBFootball yesterday.”
Fellaini has scored six goals in 25 Premier League appearances under Dutch coach Van Gaal this season.
The Belgium international has racked up just under 2,000 minutes of first-team action in the Premier League this term.
The 27-year-old was initially an unpopular signing with United fans after David Moyes snapped up the midfielder in a £27.5m deal from Everton in 2013.
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