Mike Mills happily ceded the frontman's role in R.E.M., only rarely taking over on official releases. He'd been previously described as "harmonizer-supreme," and made it abundantly clear that he never chafed in that role.

"Michael Stipe is one of the best singers in rock ’n’ roll history as far as I’m concerned," Mills once told the Guardian. "I never felt it was right to stick my voice out there, unless it was a song he didn’t care to finish."

But a deeper dive into R.E.M.'s catalog reveals Mills' Chris Squire-ish role in things: He may not be a frontman in the classic sense, but he's a perfect foil – and, when the song is just right, a smart choice to take over the mic.

In Mills' case, he brought an open-hearted exuberance to things that the darker-witted Michael Stipe couldn't always pull off. You hear it in his background vocals, to be sure, but also over and over again in these Top 10 Songs Sung by R.E.M.'s Mike Mills. We stayed away from his often-terrific star turns on the R.E.M. fan-club Christmas singles, because they aren't as widely available. Our list instead takes in many highlights from his career with R.E.M., and some key moments apart from the band, as well.

Great though they may be, this list isn't likely to change his mind about things. "It was not my job," Mills told Time magazine. "Why would I need to stick my ass out there and go, 'Hey, let's get this genius out of the way so I can start singing some more.'"

Instead, we did. Here are the Top 10 Songs Sung by R.E.M.'s Mike Mills ...

10. "Out in the Country"
From: B-side to "Bad Boy" (2003)

It's difficult to believe how many cover songs Mills took the lead on, considering his notable songwriting credits in R.E.M. – including "Nightswimming," "(Don't Go Back To) Rockville" (which he was known for singing in concert), "What's the Frequency, Kenneth?" and throughout 2004's Around the Sun. But Mills had emerged from Macon, Ga., having played in a nearly endless array over cover bands with future R.E.M. drummer Bill Berry. That helped the pair create a deeply experienced, genre-defying rhythm section on top of which Peter Buck and Michael Stipe could experiment. That these products of the rural south eventually lit upon Three Dog Night's "Out in the Country" made perfect sense, too. Later collected on R.E.M.'s Complete Rarities: Warner Bros. 1988–2011, "Out in the Country" originally rose to No. 15 on the Billboard charts in 1970 with a message of bucolic nostalgia. Mills' honey-sweet delivery is perfect for this update.

9. "When Things Was Cheap"
From: The Q People: A Tribute to NRBQ (2004)

Many R.E.M. fans discovered NRBQ – which stands for New Rhythm and Blues Quartet – during their 1990 opening gigs on the latter part of the tour behind Green. Mills could be consistently found at the stage's edge, watching as NRBQ cooked up a crazy-cool blend of roots rock, jazz, blues, oddball humor and (of course) R&B every night. R.E.M. also discussed the band on NRBQ: Rock 'n' Roll’s Best-Kept Secret, a 2003 documentary from longtime Simpsons executive producer Mike Scully. Mills must have leapt at the chance to pay it forward by singing "When Things Was Cheap," a deliriously rambling wreck of a song originally found on 1983's Grooves in Orbit.

8. "Road Runner"
From: 'Backbeat' Original Soundtrack (1994)

Mills stepped forward to cover this Bo Diddley favorite on the soundtrack for a film about the early days of the Beatles, voicing Stu Sutcliffe's spotlight moment. Collaborating with Thurston Moore, Dave Pirner and Dave Grohl, among others, Mills created a highlight moment from an album focusing on raw early rock songs that initially fired the Fab Four's imaginations. (Mills' bandmate Peter Buck once summed up their shared passion for Diddley, and what made his music so special: "What a mighty, mighty man he was, ever changing always the same.") Unfortunately, this all-star amalgam only performed live once, at the 1994 MTV Movie Awards. Their three-song set concluded with a cover of "Helter Skelter."

7. "Love Is All Around"
From: B-side to "Radio Song" (1991)

R.E.M. covered the Troggs from early in their career, reviving songs like "I Can't Control Myself" and "With a Girl Like You" for a new generation who may never have heard of the '60s-era beat-punk group. Mills and Buck originally found an old 45 of "Love is All Around" at a garage sale, Mills told the Guardian in 2014, then began playing it during practice sessions. By 1991, it had found a home in their regular setlist. "We really enjoyed playing it, so tossed it in," Mills added. They later joked publicly about recording an entire EP of Troggs songs, before Mills, Berry, Buck and long-time collaborator Peter Holsapple sat in on a Troggs album titled Athens Andover, after their hometowns.

6. "Gift of the Fathers"
From: 'Favorite Son' Original Soundtrack (2010)

This sweetly evocative track was written in honor of the late Roberto Clemente, a legendary baseball player who died in a plane crash while on a relief mission after an earthquake struck Nicaragua in 1972. Mills debuted "Gift of the Fathers" on stage before recording a new version for the closing credits of Favorite Son, a 2010 film that reunited Mills with director Howard Libov – who earlier helmed the music video for R.E.M.'s "So. Central Rain," from 1984's Reckoning. "'Gift of the Fathers' always worked great because it provides a kind of emotional release at the end of a pretty intense story," Libov later said, "and I found it just kept growing on me every time I heard it after we placed it in the film." Us, too.

5. "September Gurls"
From: Thank You, Friends: Big Star's Third Live and More (2017)

This concert film premiered at SXSW in 2017, boasting a who's-who cast including Jody Stephens (the sole surviving member of Big Star), Chris Stamey, Jeff Tweedy, Mitch Easter and Robyn Hitchcock, among others. But Mills arguably stole the show, singing one of Big Star's best-known songs with just the right touch of melancholy. His love for this band runs deep, and their influence on R.E.M. does, too. "Peter started playing these records when we hung together back in ’79," Mills told the Guardian in 2016. "I heard the first two records first, Radio City and #1 Record. I just thought they were perfect. If I could make records, that would be the sort of records I would make. The third one took me a bit longer to get into, but it does reward repeated listening. What Big Star was doing made sense to me."

4. "Mike's Pop Song"
From: Automatic for the People (1992)

Mills has claimed that this song was rejected during sessions for the often-somber Automatic for the People because if sounded too much like R.E.M. – and he's right. The aptly titled "Mike's Pop Song" would have fit much better on earlier records, instead of one Peter Buck described as "kind of a down record with a lot of minor keys," in a 2017 talk with Billboard. Still, it shouldn't have gone unreleased all together. R.E.M. corrected things when this slice of Dwight Twilley-esque power pop finally saw the light of day as part of an expanded 25th anniversary repackaging of Automatic for the People.

3. "Texarkana"
From: Out of Time (1991)

Stipe got stuck on this one, and Mills stepped in. By the time it was over, "Texarkana" had switched hands completely. "We started doing 'Texarkana,' and you can tell from the demo that Michael had started something, but then just kind of hit a wall and couldn't finish it," Mills told Garden and Gun in 2016. "I had some ideas, so I jumped in." This driving rocker eventually got tucked away on side two of an album that will always be defined, of course, by its game-changing single "Losing My Religion." (A career-best No. 4 Billboard hit, the song helped push Out of Time to the top of the album charts, too.) But this studio project was special in another way, too: It was Mills' big moment. He voiced two songs for the first time on any released R.E.M. album, and was also featured vocalist on a previously mentioned b-side on our list of Top 10 Songs Sung by R.E.M.'s Mike Mills.

2. "Superman"
From: Lifes Rich Pageant (1986)

Buck originally passed an obscure 1969 single from the Texas-based Clique over to Mills, and he and Bill Berry worked up the b-side for a jam at the 40 Watt Club. "Superman" then became the initial cover song on an R.E.M. album, the initial cover to be issued as a single, and the first released song of any kind with Mills singing lead. Michael Stipe reportedly ceded the vocals because he never liked the tune as much as his bandmates, and he famously refused to play it in concert. ("We're definitely not doing that one," Stipe told a London crowd after a fan request in 2008.) But "Superman" played an important role: This garage-band cover made it clear that Lifes Rich Pageant, released as R.E.M. was on the verge of going supernova, wasn't going to take itself too seriously.

1. "Near Wild Heaven"
From: Out of Time (1991)

A bittersweet outburst, "Near Wild Heaven" marked the first time Mills sang an original song on a released R.E.M. recording. Always modest, he played off the historical nature of it all. "'Near Wild Heaven,' it's almost a co-vocal. I guess technically I'm singing lead," Mills told Billboard in 2016. "It's just another one where we really like the song and Michael was having a little writer's block with it and he was perfectly fine with me jumping in." In truth, however, Mills made his debut count, displaying a canny knack for soaring '60s-pop on a single that reached the Top 30 in the U.K. This is R.E.M. at their shiniest and happiest, but without the corn.