Jack Harrison has been a Leeds United mainstay under Marcelo Bielsa, particularly in the last two years.
Since the beginning of 2019, Harrison has missed just two Leeds United games in all competitions, one of which he was ineligible for due to facing parent club Manchester City.
Such longevity - especially for a loan player - is extremely rare in the modern game. Factoring in Bielsa's training methods and the demands he places on his players, Harrison's consistency over the past three seasons has been rather remarkable.
That is why over the past three Leeds matches, it is quietly surprising that Harrison has missed 90 minutes - seeing himself substituted at half-time in games against Arsenal and Southampton.
Harrison has been one of Bielsa's most trusted lieutenants during the club's recent rise, so to see the Argentine call on Helder Costa from the bench as Leeds' tie with Southampton was poised on a knife-edge, was different to say the least.
There have been suggestions that the club and Manchester City may have an agreement of sorts in place to bring Harrison to Elland Road on a permanent basis at the end of the season. Harrison's non-involvement in the second halves of games in recent weeks doesn't threaten the possibility of that deal too severely, but it may cast doubt into Marcelo Bielsa's mind.
Bielsa is renowned for leaving sentiment at the door when it comes to team selection, and he would not hesitate to omit a well-established player if he deemed an alternative to be a better option.
However, the manager did not have a great deal to say on the matter in his pre-Aston Villa press conference.
"Harrison is a very strong player mentally, he’s a very dedicated professional and on occasions, as with all the players, I maintain a dialogue with him when I see fit."
For one of the first times in the past three seasons, there is a question mark over whether Bielsa will name Harrison in his starting XI this weekend.
Harrison has so far weathered calls for him to be dropped, but with Costa's return to form - two assists in three games - there is credence to suggest that Bielsa would be justified to drop an off-the-boil Harrison for the Portuguese winger.
Raphinha's ability on either flank gives him that option, and with Ahmed Elmohamady expected to start at right-back for Aston Villa, Bielsa may prioritise the Brazilian on Jack Harrison's side in order to terrorise the Egyptian.
It remains conjectural, but Bielsa's recent calls for Costa from the bench, in place of Harrison could be a window into his thinking.
Ordinarily, a player being dropped in place of another is standard practice on a game-by-game basis in football, but for Harrison - who has featured in 101 of the last 103 Leeds games under Bielsa - it could signify something a little deeper.
