By day, he works on buses. Now, he's also a Grammy-winning opera singer.

The surprise of discovering there's a Grammy winner in their midst still hasn't worn off for workers at the Motor Coach Industries Service Center in Des Plaines.

Perhaps least of all for the winner himself, heavy-duty repair mechanic and bass-baritone Andrew Craig Brown.

Brown won the Grammy in the Best Opera Recording category Sunday for his work on composer Tobias Picker's “Fantastic Mr. Fox,” as staged by the Boston Modern Orchestra Project. He recorded the piece in 2014 while still pursuing a full-time music career, but it was not released until last year.

“It was completely surreal,” Brown told co-workers who gathered with him Wednesday to celebrate his Grammy win. “I never thought something I worked on in 2014 would be released in 2019 and then nominated, let alone to win. I was just happy to be there.”

After accepting the gift of a homemade Grammy Award his co-workers assembled from an air horn and other motor coach parts, Brown serenaded the service bay with an impromptu performance of Franz Schubert's “Ave Maria.”

Just earning a nomination caught Brown off guard last November.

“Fantastic Mr. Fox” was one of three recordings he sang on during his four-year-long professional stage career, and the unexplained delay in its release often led him to doubt its quality.

When a colleague told him he'd been nominated, Brown first asked “What for?”

Though the 32-year-old Decatur native did not get to take the microphone during his visit to the Grammy stage Sunday night, he thanked his parents and fiancee when interviewed backstage immediately afterward.

He watched Sunday night's ceremony from a seat only about 40 feet from the stage, where he says he was impressed by the quality of performances from his fellow nominees.

Growing up downstate, Brown spent hours singing along to Metallica and other rock bands while riding his family's lawn mower around their rural grounds.

He believed he was faithfully reproducing their singing, but it wasn't until just before college that he sought out an independent opinion of his voice and considered music as a major. He went on to earn his bachelor's degree from the Millikin University School of Music in 2009 and his master's from Yale University in 2012.

After Yale, Brown pursued a career as a professional singer but ultimately decided to walk away from that life due to the time it kept him away from his family and uncertainty over whether his next job would be his last.

And so, relying on the in-depth knowledge of motor vehicle mechanics he'd learned from his father, he turned to the more stable work of auto repair.

“I enjoyed the work. I enjoyed the job security,” Brown said.

Cary Kadyschuk, manager of heavy-duty repair at MCI, recruited Brown from another firm in the spring of 2019, after spotting his resume online. He said Brown's combination of mechanical skills and high level of education caught his eye, indicating an intellect up to the challenge of maintaining the large and complex vehicles produced by MCI.

Brown said his Grammy win and the work ethic he's developed during his time as a mechanic have him considering a second go at the music career he feels some regret about ending.

With the permission of his supervisors at MCI, he is planning a short break from his job in June to attend a training program at the Taos Opera Institute in New Mexico.

“I'm not sure what the future holds,” Brown said. “I am not going to take this opportunity for granted.”