The Washington Nationals didn't completely overhaul their bullpen this offseason like fans might have hoped following a year where that unit finished with the worst ERA in the majors. Instead, the front office added arms on the margins, using waiver claims and minor league signings to bring new pitchers into the fold. So far, the returns haven't been great. The Nationals enter Friday with an ERA of 4.90, which ranks them No. 23 in the MLB. However, the relief staff is also coming off a series against the New York Mets where they allowed just one run across three games, so there is hope that things have started to turn around. But president of baseball operations Paul Toboni won't turn down an opportunity to add another arm. And according to Will Sammon of The Athletic , Washington has signed former Mets reliever Max Kranick to contract pending a physical.…