The A's have been, and will continue to be, busy around the edges of their roster since the last update here. In no particular order:

Edward Mujica took a batted ball off his hand, broke his thumb (apparently mildly, though tell that to Mujica's thumb), and somehow made a play on the ball to get the out before being removed from the game and basically sent straight to the disabled list. Arnold Leon had already come to the roster in place of the injured Drew Pomeranz, presumably on a short-term assignment until Pomeranz's slot in the rotation came up again and the A's brought up Kendall Graveman to make the start and sent Leon back down. Now, with Mujica getting the A's back down to seven relievers, they could have stayed the eight-reliever course and called up Chris Bassitt, RJ Alvarez, or Ryan Cook and re-optioned either that guy or Leon for Graveman's start.

Instead, for reasons not immediately obvious to me, they went for a position player, adding Andy Parrino to the 40-man roster. To make room, they had to take Tyler Ladendorf, still out with a broken ankle, off, which meant putting him on the 60-day disabled list, which means that he accrues service time and is paid major-league money, rather than minor-league money. According to Jeremy Koo, Ladendorf gets this money and service time retroactive to his injury (or, presumably, retroactive to whatever date the disabled list move is retroactive to). I haven't researched this, but it makes sense and I have no reason to doubt it.

Ladendorf's service time isn't really an issue -- he's on the career path to be a free agent by dint of designation for assignment after he runs out of options, not by getting to arbitration and six-year free agency. The money, while not some kind of burden, isn't nothing: the minimum minor-league salary for a 40-man roster player with at least one day of major league service is $81,500, adjusted by a COLA over 2014; the minimum major-league salary is $500,000, also adjusted by that COLA. Let's just call it $500,000 and $81,500, to make things easy. Ladendorf hasn't appeared in a game since April 20th, so let's suppose his DL stint (and pay) is retroactive to April 21st. Adding all that up, Ladendorf appears to be owed about $70,000. That's not a bad chunk of change! (Assuming everything I'm assuming is right, including that there is in fact retroactive pay.)

Anyway, the loss of Mujica is unfortunate. He'd looked fine, decent, solid, useful. The A's bullpen can, at this very moment, use fine, decent, solid, useful relievers. Arnold Leon may or may not be fine, decent, solid, useful. Odds are against it. Odds are he's replacement-level.

The loss of Pomeranz is more unfortunate for him, as a human being, than it is for the A's as a team that would like to win baseball games. He's pitched to an 89 ERA+. Baseball Prospectus' new pitching metric, DRA, likes him better, pegging him at 3.70 in a league scoring 4.26 R/9, which is nice mid-rotation work. Still, he hadn't done that much over his eight starts to raise serious hopes that he'd be worth an arbitration investment next season vs. filling the slot with Sean Nolin, Graveman, Bassitt, or whoever Ben Zobrist and Tyler Clippard bring back in trade next month. (What?) You can't have too much pitching, sure, but you can have too many injuries, and Pomeranz has spent a fair amount of time on the DL the last two and a half years.

In other news, Ron Washington is back to help Mike Gallego coach infielders. Specifically, he's here to work his magic on Marcus Semien, whose error situation took a turn in the last week or two from unfortunate all the way up to brutal and hard to watch. Every A's fan knows the story of Washington coaching up Eric Chavez from a bat-first, indifferent defender into a six-time Gold Glove winner, something that made the difference between a solid, above-average player on the strength of bat and position and a legitimate star, a 30 WAR player from 2001-06, someone whose fWAR for that period ranked 14th in baseball, right in between Bobby Abreu, one of the most underrated players in the game, and Derek Jeter, who I expect you've heard of. (And just behind Jeter is Jason Giambi, who made four All-Star teams and had two top-five MVP finishes in that span.) Every baseball fan, by virtue of Moneyball knows about Washington's work turning Scott Hatteberg from a "catcher" into a decent first baseman. There's some hope here, in other words, that if Semien can be made whole, Washington's the man to do it.

Susan Slusser has also been giving credit to Washington for turning Miguel Tejada from an error-prone space cadet into one of the better defensive shortstops in the league, but I think that's a massive stretch. None of the available defensive statistic suggest Tejada was anything more than a smidge above average at his best, and he may have remained solidly below average. Certainly my memory of my own eye test is that he had a prototypical arm and was solid enough but did not have the kind of range that makes someone into a top-notch shortstop. That said, Tejada did cut down on his brutal rookie error rate (26 in 526 chances, a rate that would have given him 37 in a full season of opportunities), so Washington may have done something there after all. Then again, that most basic of stats, range factor, indicates that, while he simply made fewer errors in 1999 compared to that awful 1998 total, he reached fewer balls from 2000 to 2003 than he did before the millennium turned over. That doesn't end the questions -- hell, it might not even begin them -- but there's a hint of something here that might not be simply about Washington's genius.

And then, of course, turning it back around one more time, there's the fact that Bob Melvin and Billy Beane and whoever else the decision-makers are think Washington can come in and help Semien. There's a human element, in terms of technique and communication and personality and all sorts of other factors, that doesn't simply boil down to "1. Semien has troubles; 2. Washington coaches well; 3. Let Washington coach Semien" because, hey, Mike Gallego has been around a long time, too, and has coached a lot of infielders, too, and was a pretty good defender himself, especially given his physical limitations. So I choose to be optimistic about Washington working with Semien, particularly given the reports that Semien is dedicated to that work.

Anyway, Slusser posted a photo of some work being done:

Ron Washington is already working with Marcus Semien: pic.twitter.com/i8USVXCXFA

— Susan Slusser (@susanslusser) May 22, 2015

One curiosity about Washington is that he was available to the A's at all. Here's a successful big-league manager who quit suddenly because of personal issues and he's, in May, an assistant coach at the University of New Orleans? Jeremy Koo suggested that perhaps by the time he got his personal life straightened out, teams had filled all their coaching and managing slots. That's certainly plausible, though this Evan Grant story from February suggests that Washington put the word out that he was available and found no takers. Sure, he apparently cheated on his wife, and sure, he used cocaine a while back, but this is still an 11-year major-league coach, an eight-year manager, a five-year something or other with the Mets before joining the A's. Maybe, at 63, not having been in the minors since at least 1996, he made it clear that it was the majors or bust for him, that he wasn't taking anybody's Double-A managing gig, and maybe that limited his opportunities. It's impossible to say unless he tells us, and as far as I know, he hasn't told us.

Speaking of errors, Hans Van Slooten provided me with a list showing every team back to some early date's number of errors through their first 50 games of the season. Here's the Google Doc. What's clear is that the A's are nowhere near the record. As Owen Watson showed, they are on pace for the record since 2000, but there are some notably error-prone defensive teams, even throwing out the old days, before modern gloves, defensive coaching, and manicured fields. Using the birth year of your humble blogger as a proxy for modern baseball:

Even if you cut it down to the 21st century:

I'm not going to pretend that what the A's are doing is good, but it's worth noting that they're not blowing away history.

The Brewers' Will Smith, a reliever, got suspended for having a foreign substance on his arm. Jokes ensued. This was my favorite:

Will Smith will appeal his eight-game suspension, possibly via a heartfelt apology to Aunt Viv.

— Ted Berg (@OGTedBerg) May 22, 2015

Here's today's bow tie selfie, with a cameo by the best cat in the world:

Happy bow tie Friday from me and Joey Cat pic.twitter.com/LJjeel5BEn

— Jason Wojciechowski (@jlwoj) May 22, 2015

Some good non-baseball links: The best song about fat babies; Winston Cook-Wilson on Lil Boosie; and a Storify chronicling a McDonald's date involving a 4channer.