After 20 years in the big leagues, one of the game’s grittiest and most hard-working competitors has decided to hang up his spikes and call it a career.

Love him or hate him, Curt Schilling was an institution on the mound for several Major League Baseball teams, even winning three World Series titles as a member of the Arizona Diamondbacks and Boston Red Sox.

After his two-plus decades playing the game, Schilling expressed in his blog that he had “zero regrets” about his career and had decided to retire.

He had missed the entire 2008 season with a shoulder injury.

“The things I was allowed to experience, the people I was able to call friends, teammates, mentors, coaches and opponents, the travel, all of it, are far more than anything I ever thought possible in my lifetime,” Schilling wrote.

Schilling won 20-plus games three times, in 2001 (22 wins) and 2002 (23) while with Arizona, and in 2004 (21) with Boston. He also topped 200 innings in nine of his seasons, including the 2000 season in which he split his time between Philadelphia and Arizona. His highest total came in 1998 when he racked up 268.2 innings with the Phillies.

Winning a series with Arizona in 2001 was the capping of a long struggle for Schilling, who had long been an elite player on a sub-par team. Once he was traded to the Diamondbacks in 2000, Schilling got a chance to shine. He was co-MVP of the Series in 2001 with teammate Randy Johnson.

He finished his career with a 216-146 record and a respectable 3.46 ERA.

And who could forget the infamous “bloody sock” incident, when Schilling took the mound in Game 6 of the 2004 ALCS with his ankle tendon sutured to his foot. Over the course of the game, the blood from the area began to seep through Schilling’s sock, causing him to be instantly lauded as a hero to the Red Sox nation for playing through such an injury.

I had a friend ask me today if I thought Schilling was the greatest pitcher in history who has never won a Cy Young Award. My response was: “Well, Cy Young never won a Cy Young Award … but in my opinion, Schilling would be pretty high on my list.” Not withstanding my non-commital answer to the question, it is hard to argue with a warhorse like Schilling. Say what you will about his personality, which at times could be generously referred to as “truculent,” Schilling could flat-out pitch.

As a fan of the game, I was always very interested to see what Schilling’s take on scandals would be. In 2007, during the real heat of the steroid scandal involving Barry Bonds, Schilling criticized Bonds and called his reputation into question by saying that “he admitted to cheating on his wife, cheating on his taxes and cheating on the game.” He later apologized, but it truly called into question the relationship between professional athletes. Long had I thought that they were a merry band of brothers, and that they would all agree with each other. I thought it was refreshing at the time that one star would question another star’s integrity. This is half of the reason that I always found Schilling so entertaining, not only as a player, but as a personality.

Countless things can be said about Schilling’s career, both as a pitcher and a person. But overall, if there is one thing I could say about Curt Schilling, it is this:

He was never boring.