World number one Rahm, who counts a Masters triumph among his four PGA Tour wins this season, made $839,300 for finishing second at Vidanta Vallarta, bringing his 2022-23 season total to $14,462,840.
That tops the previous record of $14,046,910 set last season by 2022 Masters winner Scottie Scheffler.
Rahm, in his second start since the Masters, was six shots off the halfway lead, fired a 10-under-par 61 in the third round to sit two shots back of leader and eventual winner Tony Finau before closing with a 67 that left three shots back.
While disappointed in falling short, Rahm said this week offered a good reminder that past results and one's standing in the world of golf are no guarantee of future success.
"A great reminder that what you've done means absolutely nothing, you still have to go out there and do it. It's also good so you don't think too much of yourself," said Rahm.
"A great reminder of what I still need to do to be able to keep winning tournaments and if you ask me, that's almost a blessing in life, to know that the work is not really done. It's never done, the search is ever ongoing."
