What happened to Nick Markakis's arm?

For several years, one of baseball's premier defenders graced the Atlanta blue-and-red. Jason Heyward debuted for the Braves in 2010, manning right field from then until 2014. Across those five seasons, he saved the team 97 runs by DRS (tops among all qualified outfielders) and 74.1 runs by UZR (also number one). Looking to rebuild in the offseason, the team dealt him to the Cardinals in a defensible move — no pun intended. Heyward will hit the free-agent market after the 2015 season, and a club such as the Braves that couldn't have contended would get little use out of him.

Confusingly, then, the Braves spent a good amount of money to bring in a replacement. Nick Markakis, who had patrolled Baltimore's outfield for nine years prior, signed a four-year, $44 million contract. At the time, Markakis brought little to the table in terms of offensive value, with a career wRC+ of 112 in 5966 plate appearances. Most of his contributions, then, would come from the other side of the ball — defense. There, the Braves wouldn't see much of a dropoff, by some appraisals:

braves actually replaced 1 gold glover (heyward) with another (markakis. the new RF, who also has GA roots, has a 4-yr deal

— Jon Heyman (@JonHeymanCBS) December 3, 2014

Obviously, that statement comes rife with problems, but in one facet of defense, Markakis actually did trump Heyward — as well as most of his contemporaries. During his career with the Orioles, Markakis racked up 93 outfield assists, the third-most in baseball. His 21 rARM (from DRS) ranked tenth, while his 21.9 ARM runs (from UZR) placed him sixth. Compared to Heyward, who had never distinguished himself in this regard, Markakis certainly looked like an upgrade.

As 2015 wraps up, we can definitively say that Markakis has downgraded the Braves. He's thrown out only four baserunners in his 1249.1 innings of work; this play has cost his team eight runs by rARM and 5.8 runs by ARM, each of which rounds out the major leagues. After his exquisite output in this regard before, Markakis has not just become average or sub-average — he's turned into a complete liability.

Baseball-Reference offers several splits for an outfielder's throwing metrics; these reveal some interesting elements of Markakis' case. First, there's the base-by-base breakdown of his assists. 96 of them have occurred while he's played in right (one came during a brief trial in left field as a rookie), and he's recorded most of them at first and second base — a trend that has continued, albeit to a lesser degree, in 2015:

Lobs to the nearer bases have still served Markakis moderately well, whereas plays beyond that have given him a lot of trouble. Essentially, he seems to have retained enough strength to cut down runners at the bases closest to him, but he doesn't possess the ability to go beyond that.

Markakis' failures at third base and home plate show up further in his hold rate. This statistic measures how often he prevents runners from moving up in several key situations*, all of them involving a throw to the two aforementioned locations. As an Oriole, he held 47.2 percent of opposing runners, about an average mark; as a Brave, he's seen that decrease to 41.0 percent. Not only has he hosed fewer men on the basepaths, but opponents have also started to test him more, and they've succeeded more when they've done so.

*Those situations: A runner tries to score from first on a double; a runner tries to score from second on a single; a runner tries to score from third on a fly ball; a runner tries to advance to third from first on a single; and a runner tries to advance to third from second on a fly ball.

We can also examine Markakis' play on a game-by-game basis, which helps to counteract one theory regarding his decline. In the offseason, he underwent surgery on his neck, which kept him out until late in Spring Training. On Monday, Atlanta manager Fredi Gonzalez posited that this accounts for most of Markakis's struggles:

"I think the whole game will come back," Gonzalez said. "I think you’ll see his arm strength even come back, I really do. Because what did he have, two weeks (of games) in spring training? And really, going into that it was nothing. He couldn’t do anything..."

While this looks like a reasonable theory, Markakis has done even worse as the year has gone along. He notched his fourth assist of the year on July 3rd, when he fired this bullet to retire Cesar Hernandez attempting to stretch a single into a double. At that point, he had played 685.0 frames, meaning his assist rate on a per-1000 inning basis stood at a satisfactory 5.8 — not terribly worse than the standard of 7.9 he set for himself in Baltimore. Since that day, however, he's endured a 564.1-inning assist-less stretch, which has drained any value he accrued before. Had the lack of preparation significantly harmed Markakis, we'd expect him to progress with more time under his belt; instead, he's just fallen further behind.

Obviously, a herniated disc in one's neck (along with a sore trapezius, as the above article outlines) won't help one's throwing capacity. Assuming Markakis doesn't encounter any setbacks in his recovery, some of his abilities should return. He will turn 32 in November, though, so that healing might not come as quickly as the team would like — and even if it does, the natural effects of aging could cancel it out. Whatever happens, it appears as though the Markakis of old, whose strong arm in right kept the opposition honest, won't come back.

Whatever team signs Heyward will receive an elite defender as well as a quality outfielder overall. Once upon a time, the Braves could lay claim to that; now, though, they must watch as Markakis repeatedly fails to make tough catches. And unlike in past years, he probably won't make up for that lack of range with his arm. The next three years in Atlanta likely won't feature many great defensive outfields.

. . .

All data as of Tuesday, September 22nd.

Ryan Romano is an editor for Beyond the Box Score. He also writes about the Orioles on Camden Depot (and on Camden Chat that one time) and about the Brewers on BP Milwaukee.