The insane testing process behind Collin Morikawa's iron switch for The Open

Collin Morikawa isn't a man you'd associate with needing help with ball-striking, but the firm conditions at The Open Championship this this week had even the American searching for a new way to approach this weekend's play.

The world number seven has confirmed a switch in his irons for this week, swapping out his usual TaylorMade P·7CB irons for a set from the P·7MC model — an iron with a narrower sole geometry and ostensibly less forgiveness.

Why then, with Royal Birkdale presenting some of the firmest, tightest lies set to be seen on tour this year, would Morikawa switch into a harder-to-hit iron? The answer came from one of the most unconventional testing processes we've heard about thus far.

Adrian Rietveld, TaylorMade's Senior Tour Manager, provided a full deep-dive into the testing process for a piece on the brand's tour blog.

"At the British Open, Collin has a deep understanding of how links turf differs from almost every other style of golf course in the world," said Rietveld. 

"Links turf is significantly firmer, the grass is tighter, the club enters and exits the ground differently, and the margin for error becomes much smaller. A sole that performs beautifully on softer American parkland conditions can become noticeably less efficient on the firm, running surfaces found at British Open venues."

"In true Collin fashion, his testing methodology was unlike anyone else's," "Rather than simply hitting golf balls and judging feel, he took both sets onto a cart path at home."

What the testing revealed, essentially, boils down to the way the P·7MC's narrower sole geometry reacts with firmer surfaces, Morikawa going so far as to test irons on a cart path to more effectively mimic the baked-out links turf at Royal Birkdale.

"While this may initially sound unusual, it actually provided an incredibly consistent testing environment. Sliding each club along the firm path immediately highlighted exactly where the sole was contacting the surface. Every mark on the sole represented a point of ground interaction, allowing him to visually study how each grind, relief area and leading edge would engage the firm ground."

"By comparing the wear patterns between the different sole geometrics, Collin was effectively able to visualise how each iron would behave on links turf before arriving in Southport."

Of course, we don't recommend you do the same at home if you value the look of your irons.