The Northern Irishman finished two shots behind England's Cameron Smith in the DP World Tour Championship final leaderboard.
Hatton's closing six-under-par 66 helped him romp to a five-shot victory on 15 under par but most eyes were on the thrilling battle that went down to the final hole.
Chacarra, the 26-year-old world number 39, finished in a tie for third to end up second in the overall standings and earn a PGA Tour card for next season.
Moments after matching Colin Montgomerie's record of season-long European tour titles on Sunday, the Northern Irishman was asked about the health of his father.
It was that head-to-head battle between Schauffele and McIlroy that dominated the tournament, a battle that, after a long hard season, came right down to the wire.
But a late surge from Northern Ireland's McIlroy allowed him to finish runner-up behind England's Hatton in the tournament and collect enough points to edge out the gutsy Spaniard.
As tough as it was this year for McIlroy to win, mainly due to playing on the PGA Tour for the first half of the season, 2027 will be even harder because there will be some big names flooding in after the collapse of LIV Golf.
They will both have a full season on the European circuit that will give them a big advantage over McIlroy.