The adjustment has been made. Jae Weong Seo, one-time NL Rookie of the Year candidate, now must counter.

Yesterday, the misery continued as the Cardinals took away Seo’s best weapon, the change-up, in their 10-9 victory over the Mets at steamy Shea.

Bo Hart’s fourth-inning fully illustrated the change-up problem. With the bases loaded with Cardinals, Hart – who is listed at 5-11 in the Cardinal media guide, but is probably about three inches shorter – saw two changes float by. One for a strike, one for a ball.

Jason Phillips, who caught for the Mets, thought about going to the change-up for a third-straight time. Instead, trying to outguess Hart, Phillips chose the slider, which is not Seo’s best pitch.

“It was a slider that didn’t slide,” Seo said.

The ball landed over the center-field wall. Hart’s grand slam led to Seo’s undoing, continuing a horrendous run in which he has fallen out of the Rookie of the Year race, and perhaps even put into question if he is a top-half of the rotation-type of starter.

In the middle of June, Seo owned a 2.66 ERA, which led to an impressive 5-2 record. Since then, Seo has been worse than the reviews of “Gigli.” He is 0-6 with two no-decisions – incidentally, they were also Met losses – and his ERA is an unsightly 7.97.

The reason for much of trouble is that hitters are just sitting on that change. Major-league hitters have adjusted to facing him. They have taken away the change to some degree by focusing on it.