get into someone's head

Yet unlike many of Jackson’s supporters, he would not label his fellow senators racist. “I’m not going to try to get into the head of my colleagues to understand what’s motivating them. It’s a fool’s errand,” he told me.

Even more incredibly, he defended it last month, brushing aside the formidable world No 1, Michael van Gerwen, in the process. The Dutchman, still overwhelmingly the man to beat, firmly denies the upstart challenger has got into his head. Which is probably an admission that he has, a little bit.