This has not been a banner week for player-umpire relations. On Tuesday, the Major League Baseball Umpires Association vented on social media about San Diego Padres third baseman Manny Machado receiving only a one-game suspension following his weekend ejection in which he may have made contact with home-plate umpire Bill Welke. On Thursday, San Francisco Giants catcher Buster Posey criticized replay officials, saying they have "no accountability."

Manager Bruce Bochy added his own choice words as well:

Posey and Bochy's disgust stem from a call made during the ninth inning of a game against the Los Angeles Dodgers. The Giants trailed by a run and had runners on first and second with nobody out. Tyler Austin laid down a bunt, but Dodgers first baseman Cody Bellinger fired to third and was rewarded with an out call. The Giants challenged, hopeful that Stephen Vogt had slid in ahead of the thread, yet the replay officials deemed otherwise. The Dodgers would retire the next two batters to win the game.

Take a look at the play in question:

Plays don't get much closer than that. It does appear Vogt may have beat the throw, albeit by a hair. As such, you can understand Posey's annoyance. The Giants had rallied late against a rival, and this call eliminated a game-tying sacrifice fly from the possibility tree. Who knows whether the Giants tie or rally had Vogt been called safe, but they could have had the bases loaded with nobody out -- a bases-out situation that yields more than two runs on average.

What's more is the Giants have not been a successful team at challenging calls. Just two of Bochy's 10 attempts have resulted in an overturn, the worst rate in baseball. For reference, every other team -- including Cleveland, who has asked for fewer challenges -- has had at least four calls overturned. Overall, the league-average rate is about 54 percent.

To Posey's point about accountability and whatnot, a cynical would note there is room for conflict of interest. Replay officials are full-time umpires who rotate through the command center. If they overturn too many calls, they make their colleagues look incompetent. Of course, the catch is that a high overturn rate would also mean that teams aren't taking enough chances with their challenges -- it's akin to having a third-base coach whose sends are safe 100 percent of the time; that means they're sending only on sure things, which isn't the optimal strategy.

Perhaps the real takeaway from all this, then, is that instituting replay was never going to be as simple as "getting calls right."