In the early weeks of the PGA Tour’s new driver testing program for the 2019-2020 season, a handful of players appear to have had drivers tested that have exceeded the speed limit. According to a story from Reuters, written by veteran Australian golf writer Andrew Both, five tour pros at last week’s Safeway Open were found to have drivers whose spring-like effect was outside the R&A/USGA limit.

The tour’s new protocol uses the pendulum test that measures the Characteristic Time (CT) of driver faces to determine whether they flex too much. The Reuters story named five players it says are “believed” to have drivers that did not pass the test: Corey Conners, Jason Dufner, Mark Hubbard, Robert Streb and Michael Thompson.

The tour’s driver testing program grew from concerns expressed during the past year that driver faces are getting springier through use. The issue drew headlines when the R&A selectively tested drivers at the Open Championship at Royal Portrush in July and several clubs were found to be over the limit, most notably that of Xander Schauffele.

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Tyler Dennis, PGA Tour senior vice president and chief of operations, told Golf Digest earlier this year that the testing program is an effort to investigate whether drivers that were conforming at initial use can be worn into a non-conforming state over time.

“We really want this to be about the driver models currently being played on the PGA Tour, not the players,” Dennis said earlier this month. “We have seen evidence of some models that over time are starting to creep over the limit. The only way to understand what’s happening is to test drivers that are actually being played on tour.”

The protocol calls for random player testing to be conducted during non-competition days at unannounced tournaments. Dennis would not specify how many players would be tested at events or how many events would have testing implemented. According to the Reuters story, 30 drivers were tested in California.

Dennis did not immediately return a request for comment on the report of drivers failing the CT testing at the Safeway Open. A tour spokesman told Reuters the tour would not be commenting on the testing program or its results.

Under the testing protocol, drivers receive either a green light for those that measure under the CT limit of 239 microseconds, a yellow light when they measure within the CT test’s tolerance zone of 240-257 microseconds and a red light if the measurement is above 257 microseconds. The testing on the PGA Tour is conducted by representatives of the USGA.

RELATED: Tour pros don’t sound too concerned about the PGA Tour’s new driver testing protocol

Most insiders agree on two things with regard to the CT testing: firstly, there are extremely few drivers on the tour that would measure green on the CT test. Most are likely to register yellow, at least. Secondly, the difference in terms of distance is negligible, and that even if every driver on the tour suddenly measured green, there would likely be no effect on the driving distance average on the PGA Tour.

Driving distance on the PGA Tour was down for the 2018-2019 season by two metres in 2019 versus 2018. Through the early part of the 2019-2020 season, driving distance is 278.3 metres (304.4 yards). That would be nine metres longer than last year through a similar number of events, and almost 10 metres longer than 2017.

After the 2017 season, golf’s ruling bodies expressed concern about driving distance and announced a Distance Insights research project. The project’s initial report is due later this year.