To say there’s uncertainty surrounding starting pitching heading into the 2021 season would be an understatement. No pitcher threw more than 84 regular-season innings in 2020, and only five pitchers even threw more than 75 innings. Workloads will be closely monitored and the value of a stalwart starter who will go deep into games becomes even more important -- especially from the fantasy perspective.

Fantasy owners may be inclined to draft a starter earlier than they usually would have in past years, to ensure having one to rely on. The eternal question between a known, proven, but aging starter compared to a younger one who may end up throwing fewer innings will have a big impact on fantasy seasons.

Here's a look at the top fantasy options at starting pitcher via MLB.com's 2021 rankings.

Tier 1: Gerrit Cole, Jacob deGrom, Shane Bieber

Talk about three aces. Tier one is loaded, as expected, and all three of these star starters will net you plenty of strikeouts.

Cole has 696 strikeouts since the start of 2018, 61 more than any other pitcher in that span. He’s posted a sub-2.90 ERA in each of the past three seasons, including a 2.84 mark in 73 innings in his debut season with the Yankees in 2020.

The other two members of this top tier have combined for three Cy Young Awards since 2018: deGrom in 2018-19 in the National League and Bieber in 2020 in the American League. deGrom somehow continues to add velocity to his fastball, and in 2020, he led all pitchers in 99-plus mph pitches with 192. He reportedly hit 102 mph in a Spring Training start this year.

Bieber struck out 14 on Opening Day in 2020, tying for the second most in an Opening Day outing, and was off, setting strikeout records abound, including the most in a starter’s first 50 innings in a season. He was already a burgeoning ace heading into ‘20, and his MLB Triple Crown cemented that.

Tier 2: Lucas Giolito, Walker Buehler, Trevor Bauer, Aaron Nola, Max Scherzer, Yu Darvish, Jack Flaherty, Clayton Kershaw, Luis Castillo, Zac Gallen, Brandon Woodruff, Tyler Glasnow, Blake Snell

This tier features four pitchers who have won a Cy Young Award in their careers, in Bauer (2020), Scherzer (2013, 2016-17), Kershaw (2011, 2013-14) and Snell (2018). And the others? They’re pretty much all guaranteed to end up on Cy Young prediction lists in 2021 and beyond. Even outside of the top three noted above, these pitchers are a strong group.

Giolito’s turnaround from 2018, when he had the worst ERA among qualified starters, to 2019, when he finished with a 3.41 ERA and was an All-Star, continued in ‘20. He no-hit the Pirates on Aug. 25, setting a franchise record for strikeouts in a no-hitter with 13. ZiPS projects him for 248 strikeouts in 2021, second most in the Majors behind Cole -- and ahead of Bieber.

Castillo is a strikeout artist with his changeup. He has 207 punchouts on the pitch over the past two seasons -- 101 more than the next pitcher on the list, who happens to be Giolito. Speaking of notable pitch types, Buehler’s four-seamer was one of the most valuable in 2020, according to Statcast’s run values, as was Darvish’s cutter and Kershaw’s slider.

Gallen has been such a popular dark horse Cy Young pick, that it’s hard to even view him in that light anymore. He’s just a bona fide candidate at this point. He succeeds on the edges of the zone, and he has evoked Greg Maddux comparisons -- talk about high honors.

Tier 3: Kenta Maeda, Sonny Gray, Lance Lynn, Corbin Burnes, Dinelson Lamet, Carlos Carrasco, Max Fried, Zach Plesac, Stephen Strasburg, Hyun Jin Ryu, José Berríos, Jesús Luzardo, Zack Greinke, Zack Wheeler

Lynn has thrown 292 1/3 innings since the start of 2019, most in the Majors. That kind of reliability will always be at a premium, but even more so in a year like 2021. Greinke is fifth on that same list.

Lamet has lingering injury concerns, but if he’s healthy, his slider will be a key component to his success. It was the most valuable pitch in the Majors last year by a fairly wide margin, per Statcast’s run values. Opponents hit just .080 in at-bats ending on the pitch, with a .120 slugging percentage.

Fried allowed just a 24.5% hard-hit rate in 2020, the lowest of 101 qualified pitchers. Along with limiting hard contact, he kept the ball in the ballpark, allowing just two homers in the regular season.

Tier 4: Sixto Sánchez, Kyle Hendricks, Dylan Bundy, Ian Anderson, Lance McCullers Jr., Patrick Corbin, Chris Paddack, Pablo López, Charlie Morton, Germán Márquez, Sandy Alcantara, Julio Urías, Frankie Montas, Kevin Gausman, Joe Musgrove, Marco Gonzales, Mike Soroka, David Price, Chris Bassitt, Triston McKenzie, Dallas Keuchel, Tyler Mahle, Corey Kluber, Dustin May

Sánchez throws heat. He averaged 98.5 mph on his four-seamer in 2020. But his strikeout pitch was his changeup, which was his most frequently used pitch. He got 18 strikeouts on it last year.

Hendricks may not be a go-to pick for strikeouts, but he’s definitely worth keeping an eye on for ERA. His 2.88 ERA in the shortened 2020 season was his lowest since 2016, and he’s never posted an ERA above 3.95 in his seven-year career, with six of those seasons coming in below 3.50.

Soroka is one to watch returning from injury after tearing his right Achilles tendon early in the 2020 season. He, too, is less of a strikeout pitcher, but he is still effective, with a 2.68 ERA in 29 starts in 2019, when he finished second for NL Rookie of the Year and received Cy Young consideration.

Kluber is another starter who missed most of last season with injury, but in his case, he also missed most of 2019. It’s hard to gauge exactly where his innings count may fall, but if he’s back to the 2018 and prior version of himself, the Yankees will potentially have another ace-level pitcher along with Cole.

Tier 5: Jordan Montgomery, Andrew Heaney, Aaron Civale, Elieser Hernandez, Marcus Stroman, Cristian Javier, Jameson Taillon, Zach Eflin, Chris Sale, James Paxton, John Means, Drew Smyly, Jose Urquidy, Tony Gonsolin, Eduardo Rodriguez

Innings may be a question with a handful of these starters, but there are still great choices to be had even in the later rounds of drafts. Stroman has looked good so far in Spring Training, and he's primed to own the No. 2 spot in the Mets’ rotation. Taillon, like Kluber, is a bit of a question mark for the Yankees with the potential to be a strong contributor.