Rory Mcllroy faces fine from the European tour for throwing his club in frustration following a poor second shot to the 17th during the opening round of BMW PGA Championship at Wentworth.
The world number one said that he was fighting to keep his emotions in check after getting "a little angry", the BBC reported.
Mcllroy added that physically he was all right, but mentally he could feel himself getting a little angry.
The defending champion, who threw his club in frustration, is six shots behind leader Francesco Molinari at Wentworth.
Mcllroy, who won his 11th PGA tour in the United States at the Wells Fargo Championship last week, hit three bogies in the round of 71 despite perfect weather conditions.
However, this is not the first incident this summer when Mcllroy was in trouble, with the world number one throwing his three iron into a lake at Doral during the WGC-Cadillac Championship in March.
