If you like baseball uniforms and enjoy looking at the changing styles, designs and colors over the decades, you've probably spent some time getting lost in the Hall of Fame's online uniform database, "Dressed to the Nines."

And for that, you have Marc Okkonen to thank. It was Okkonen's book, "Baseball Uniforms of the 20th Century," published in 1991, that became the basis for the database. Okkonen passed away on Monday at age 85 after a short illness.

According to the Society for American Baseball Research, Okkonen's interest in uniforms was sparked by "The Natural." The movie came out in 1984, the year Okkonen's favorite team, the Tigers, won the World Series.

"I knew some of [the uniforms in the movie] were wrong," Okkonen once said. "I think that was the spark that sent me on my research."

Okkonen's research for "Baseball Uniforms of the 20th Century" took him from his hometown of Muskegon, Mich., to libraries in Los Angeles and Washington, and he even moved for a time to upstate New York to have easier access to the library at the Hall of Fame. The result was a book of nearly 300 pages containing full-color images of every team's uniform, year by year, along with franchise overviews and photographs.

In addition to his research on uniforms, Okkonen published "scrapbooks" of the early decades of the 20th century, an illustrated history of the career of Ty Cobb and the first history of the short-lived Federal League. Another book, "2,000 Cups of Coffee," featured images and basic details -- debut date, birth and death dates, Minor League teams played for -- of players from 1900-49 whose Major League careers consisted of 10 games or fewer. 

Okkonen also turned his attention to his hometown, writing a history of baseball in Muskegon and serving on the board of directors of the local sports hall of fame. In the summertime, he could often be found in the bleachers at Marsh Field, watching the Muskegon Clippers of the Great Lakes Summer Collegiate League.

Paul Lukas, creator of the Uni Watch website, credits Okkonen with the current state of uniform interest and awareness.

"The throwback craze would probably never have developed the way it has if not for Okkonen, for example," Lukas wrote in a tribute. "And it almost goes without saying that the other great uniform databases -- the Gridiron Uniform Database, NHLuniforms.com, and The Game Worn Guide to MLB Jerseys, Threads of Our Game -- are all descended from Okkonen’s original work."

In 2014, SABR presented Okkonen with its Henry Chadwick Award, which honors baseball researchers for contributions linking America's present with its past.

"By turning his artistic eye to baseball and pursuing his passion, Marc Okkonen left baseball researchers with a singular legacy," Daniel R. Levitt wrote at the time. "He created several books that captured baseball’s eras and leagues, enhanced and made indispensable by the numerous photos and illustrations he unearthed. But most importantly, Okkonen’s research delivered a comprehensive and visually appealing illustration of baseball uniforms from the twentieth century."