If UFC president Dana White had any hair left, the rest of it likely would have fallen out Wednesday as another fighter pulled out of a high-profile fight due to injury.

SB Nation sister site MMA Fighting is reporting that middleweight Brian Stann hurt his shoulder in training and is now out of his UFC on Fox 4 August main event with Hector Lombard. The injury will not require surgery, but he will be out for the next 6-8 weeks.

The 31-year-old Stann (12-4) was coming off an April TKO win over Alessio Sakara, rebounding from his one-sided loss to Chael Sonnen last October. He's won four of his last five.

The 34-year-old Lombard (31-2-1-1) was set to make his UFC debut on the Fox show, his first fight since the promotion signed him away from Bellator Fighting Championships. He is on a 25-fight unbeaten streak and left Bellator as their 185-pound champion.

On a nearly daily basis, the UFC has had fighters reporting injuries that have caused fights to get changed around, canceled and put on pause until new opponents are found. Vitor Belfort, Jon Fitch, Thiago Silva and Thiago Alves are just four of the recent high-profile fighters that Stann joins in the injury ward.