In an injury that could have wide-ranging ramifications for the San Francisco Giants this season, set up man Will Smith has been diagnosed with a sprain and strain of his left UCL and will likely undergo further testing to see if he needs Tommy John Surgery. 

At the very least, Smith is out for Opening Day. And in reality, the above-mentioned surgery is not completely out of the question here. 

Smith, 27, performed extremely well for San Francisco after coming over from the Milwaukee Brewers in a mid-season deal last year, posting a 2.95 ERA and 1.20 WHIP in 26 appearances. 

Given just how poorly the Giants' bullpen performed last season, any injury will impact the team's rotation a great deal.

Remember, last season saw San Francisco blow the most saves in the bigs with the likes of Madison Bumgarner, Jeff Samardzija and Johnny Cueto being impacted big time.

The three combined to take losses or receive no-decisions in 22 starts in which they yielded two earned runs or less last season. 

The good news here is that San Francisco did add All-Star closer Mark Melancon to the mix during the winter. The bad news? There's now a whole heck of a lot of question marks behind him in the bullpen. That should lead to questions regarding the top-end fantasy relevance of the Giants' otherwise dominant rotation.