A month after his split from Jessica Biel, Justin Timberlake has a new hair-raising dilemma.

According to a pal, the single star, 30, who was once known for his mop top, is horrified by his thinning mane – which could easily ruin his dating game. "He's keeping his hair super-short so no one notices," the friend tells In Touch.

But Justin, who was spotted cozying up to starlet Olivia Wilde in LA on April 2, isn't letting go without a fight. "He's using specially formulated shampoo to promote hair growth," the friend adds. "He certainly doesn't want to go bald!"