The seemingly never-ending drought without live Major League Baseball games has come to an end. Sunday marks the official start of 2021 spring training exhibition games, with both the Cactus League (Arizona) and Grapefruit League (Florida) seasons kicking off. Here's the full schedule.

The Grapefruit League schedule has been altered to reduce travel amid the coronavirus pandemic. Spring training games were originally set to being on Saturday, but were pushed back a day after the league revised the schedule. The league and the players have worked out both rule changes and COVID-19 health and safety protocols for the season, and spring training will have a different look in 2021.

Because of the still ongoing COVID-19 pandemic, fans weren't permitted to attend MLB games last season until the very last rounds of the playoffs. This season, however, figures to occasion more of an atmosphere of normality in this regard. The plan right now is for fans to be in attendance at spring training games and regular season games, albeit in limited numbers and in accordance with local guidelines.

As of now, the league's plan is to complete spring training in its entirety and prepare for a full, 162-game season with 2021 Opening Day scheduled for April 1. As far as getting you primed and ready for baseball this year, CBS Sports has you covered with 10 crucial position battles for contending teams, four young players with something to prove in 2021, one breakout candidate from all 30 MLB teams as well as 10 storylines to watch for during spring training.

Now, in honor of all the baseball action returning, we're highlighting four things to watch on the opening day of spring training.

1. Arenado in red

Nolan Arenado
STL • 3B • #28
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The St. Louis Cardinals' new third baseman, Nolan Arenado, is set to make his debut at the hot corner in Sunday's spring training game against the Washington Nationals. The Cardinals landed Arenado in a blockbuster trade with the Colorado Rockies earlier this winter and are the favorites to capture the NL Central in 2021.

Arenado, who's going into his age-30 campaign, will be able to use spring training to start building in-game chemistry with his new infield mates, first baseman Paul Goldschmidt, second baseman Tommy Edman and shortstop Paul DeJong, in St. Louis. The five-time All-Star boasts an elite combination of power and value in the field, and will be a huge upgrade for the Cards, who could take back the NL Central in 2021, a division they won in 2019.

And, keeping with the Cardinals...

2. Flaherty on the bump Sunday

Jack Flaherty
DET • SP • #9
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Unlike actual Opening Day, the first day of spring training game does not feature every team's ace. However, Cardinals No. 1 starter Jack Flaherty will be the biggest name to make a start Sunday. The right-hander was awarded the Opening Day nod at the start of spring training and he'll also get the ball for the Cards' Grapefruit League opener against the Nationals. St. Louis manager Mike Shildt said that Flaherty will likely work two innings in his first outing of the spring.

Flaherty, 25, had a bumpy 2020 season due to the Cardinals' coronavirus outbreak that led to a 25-day long shutdown for the right-hander. All in all, Flaherty recorded a 4.91 ERA (ballooned after one bad outing vs. Brewers in September) in 40 1/3 innings during the 60-game season. Take out the rough Brewers outing, and Flaherty's ERA is 3.14. As far as strikeouts go, Flaherty still posted a 10.9 K/9 rate over the small sample size of 2020.

Marco Gonzales of the Mariners and Zac Gallen of the D-Backs are other notable starters who will pitch Sunday.

3. New faces in new places

Like every year, spring training games give us a minute to adjust to seeing players with new teams. If we're being honest, it can take a while to get used to a player sporting a new uniform. For the first day of spring training games, we'll be seeing a handful of players make their debut with a new squad. While there's still plenty more waiting to make their debut, Sunday will see Marcus Semien with the Toronto Blue Jays, both Andrew Benintendi and Carlos Santana with the Kansas City Royals and Enrique Hernandez with the Red Sox, among others.

Semien, our No. 11 free agent this winter, signed with the Blue Jays on a one-year, $18 million deal. The 30-year-old is set to take over at second base for Toronto since Bo Bichette is their everyday shortstop.

Benintendi, 26, was traded from the Red Sox to the Royals in a three-team trade that also included the Mets. He struggled in 2020 before being shut down with a rib injury. He'll start in left field Sunday for Kansas City. CBS Sports ranked Santana, 34, as the 45th-best free agent available this offseason. The veteran first baseman signed a two-year, $17 million deal with the Royals, filling a big hole at first for the club, and now he should be an everyday staple in the middle of Kansas City's lineup.

4. Trey Mancini's return

Trey Mancini
MIA • RF • #13
*Stats from 2019 MLB season
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The best feel-good story to come out of this year's spring training is Baltimore Orioles outfielder/first baseman Trey Mancini's return to the baseball diamond following a battle with stage 3 colon cancer

Mancini will be in the lineup for Sunday's game against the Pittsburgh Pirates. Mancini missed the 2020 season, but the last time he played, in 2019, Mancini had a breakout season in which he set career-highs in home runs (35) and OPS (.899). Mancini made his MLB debut in September 2016.

Mancini, who turns 29 next month, was diagnosed with stage 3 colon cancer last Marchunderwent surgery to remove the malignant tumor from his colon and completed his scheduled chemotherapy treatments in September. The Orioles announced that Mancini is 100 percent healthy and Mancini was able report to Baltimore's camp in Sarasota, Florida. with no restrictions. For 2021, Mancini will likely see most of his reps at first base. Orioles manager Brandon Hyde is planning to rotate Mancini between first and designated hitter every other day for the early part of spring training.

Mancini currently serves on the Colorectal Cancer "Never Too Young" advisory board, which advocates for all young onset patients and survivors.