By Matt Smith ABU DHABI (Reuters) - World number one Jordan Spieth was left bemused after becoming the first high-profile player to receive a "monitoring penalty" for slow play in the opening round of the Abu Dhabi Golf championship on Thursday. The 22-year-old American, playing with four-time major winner Rory McIlroy and compatriot Rickie Fowler, was warned after taking too long to putt on his eighth green -- despite the following trio lagging far behind his group. “It didn’t make any sense to me,” Spieth told reporters after his four-under round of 68. More...