A comprehensive history of professional baseball players named Matt Ryan

Matt Ryan is a pretty common name. According to the Census Bureau, there were 139,335 people in the United States with the surname Ryan in 2000, and the social security administration says Matthew has been a top-20 name for baby boys since 1980. It stands to reason that there have been, and are, a lot of Matt Ryans in the world. One of those Matt Ryans is Atlanta Falcons quarterback Matt Ryan, who played baseball in high school, but stuck with football in college and beyond -- which was probably a good call, since he's playing in the Super Bowl on Sunday. Other Matt Ryans, though, have played professional baseball.  
Using Baseball Reference's historical database of professional ballplayers, let's take a look at the history of Matt Ryans in baseball.
Matt Ryan, Alameda Greys (1906)
Allegedly, a Matt Ryan played for the Greys in the then-independent California League. The first Matt Ryan in professional baseball, according to B-Ref, played with teammates named "Wallace" and "Goldsworthy."
Matt Ryan, MiLB (1993-2000)
It was 87 years before another Matt Ryan got paid to play baseball. In the 25th round of the 1993 MLB Draft, the Pirates selected a pitcher out of the University of Mississippi named Matt Ryan (fun fact: a few picks before Ryan, the Dodgers selected All-Star catcher Paul Lo Duca). Apparently, his first name is actually William, but he goes by Matt so he counts.
Ryan's career started well -- he had a 2.21 ERA and 45 strikeouts over 36 2/3 innings in his first year -- but after eight seasons in the Minors, he never made it to the big leagues. He spent every year but his last with the Pirates organization, and finished with a 3.26 ERA and 338 strikeouts over 489 career innings.
Matt Ryan, Arizona Fall League (2005-06)
The third Matt Ryan was signed by the Angels as a free agent out of Australia and played two seasons in the Arizona Fall League in '05 and '06 as a 19 and 20 year old. That's the extent of his professional baseball career in the United States -- he finished with four homers in 78 games -- but he did play in the Dutch Major League in 2010.
Matt Ryan Kemp, MLB (2006-Present)

Did you know Matt Kemp's middle name is Ryan? That makes him, in one way, another Matt Ryan in professional baseball, even if he rarely goes by his full name. Kemp is a two-time All-Star who finished second in National League MVP voting in 2011. Now with the Braves after last season's deadline deal with the Padres, perhaps he will start using his middle name more often if the Falcons win the Super Bowl.
Matt Ryan Joyce, MLB (2008-Present)

A second MLB Matt, Matt Joyce, also has Ryan as a middle name. Like Kemp, he too was an All-Star, for the Rays in 2011. 
Bonus: Ryan Mattheus, MLB (2011-15)

There are a few MLB Ryans whose middle names are Matthew -- Church, Doumit, Goins among them -- but honestly, that's a step too far. Ryan Mattheus (pronounced like Matthews), however, is close enough. Mattheus was drafted by the Rockies in 2002, pitched out of the bullpen for the Nationals, Angels and Reds and spent 2016 with the Triple-A Louisville Bats.