Definition: In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
Input: Moeen Ali suffered a sickening blow to the back of his head in an area that would have been protected by a 'StemGuard', additional helmet padding that he'd chosen not to wear. Makeshift opener Moeen was hit in the second over of England's second innings when he misjudged a short ball Wahab Riaz, which he ducked into while turning his head. He was hit just below the back of his helmet in a similar spot to that which claimed the life of Australian Phillip Hughes at the Sydney Cricket Ground last year. Pakistan's fielders showed genuine concern as Moeen fell to the ground on impact before getting up quickly, before a replacement helmet and medical attention came out.Moeen Ali was hit in the back of the head by a short ball from Wahab RiazBall hit England's opener in the area that would be covered by StemGuardAfter being hit, Moeen attached the additional protection to back of helmetMoeen, hit in the second over of the inning, was out LBW for 22England are 46 for two at stumps on day four, chasing 284 for victory 
 Question:Any time a batsman gets hit on or around the helmet is extreme cause for concern these days in the wake of _' tragic death.

Phillip Hughes