The John Deere Classic could serve as a final qualifier for The Open Championship, even though The R&A no longer offers an exemption to the leading finishers at the PGA TOUR stop.

This qualifier would be determined by the Official World Golf Ranking next week.

The 156-man field for Royal Portrush on July 17-20 is now at 122 players with the addition of two spots from the Italian Open, two amateurs (European Amateur and Open Amateur Series) and Sergio Garcia getting the lone spot from LIV Golf.

Final regional qualifying Tuesday in the United Kingdom provided 20 spots. Five more players from the top 20 in the Race to Dubai on the DP World Tour will earn spots after this week’s BMW International Open in Germany. The following week, three more spots will be available in the Genesis Scottish Open.

That brings the field to 150 players. The other six would come from a reserve list, which is based on the Official World Golf Ranking published after this week.

Aldrich Potgieter won the Rocket Classic and moved to No. 49 in the world, making him the highest-ranked player not already in The Open. He is followed by Nico Echavarria, who tied for sixth in Detroit and moved to No. 51. Next on the list is Michael Kim at No. 55.

Seven of the next eight players in the world ranking not already exempt for The Open — from Bud Cauley at No. 59 to Ryan Gerard at No. 71 — are playing the John Deere Classic. Davis Riley is not in the John Deere field.

If it plays out that way, in some respects it would make up for the fact that no one from the PGA TOUR qualified from the category that exempts the leading five players from the top 20 in the FedExCup standings through the Rocket Classic.

The top 28 players in the current FedExCup standings already are exempt, eight of them because they already were in the top 50 at the May 25 cutoff. Seven of those 28 were eligible by reaching the TOUR Championship last year, and nine others got in as past major champions or from a top-10 finish at The Open last year at Royal Troon.

It was only the second time in the last 10 years that everyone from the top 20 in the FedExCup was already exempt. Typically, no more than two or three came out of that category.