Did you miss last year’s 50th anniversary of the release of “ABC” by the Jackson 5? Yeah, me too. But, in honor of that catchy tune, I’m gonna teach you, teach you, teach you … about the upcoming baseball season. Opening Day for the Boston Red Sox is Thursday, and the Portland Sea Dogs return to Hadlock Field in early May.

A is for Alex. In this age of the cancel culture, it is nice to see Alex Cora get a chance at redemption, managing the Red Sox again after serving a one-year suspension for his role in the Astros’ sign-stealing scandal of 2017. And, more to the point, Cora is good at his job, with his knowledge of the game, his communication with players, and his ability to calmly manage in the pressure cooker of Boston.

Boston’s Bobby Dalbec leads the major leagues with seven home runs in spring training. Steven Senne/Associated Press

B is for Boom, as in Bobby Dalbec. He could be Boston’s best homegrown power hitter since Mo Vaughn (230 homers for the Red Sox from 1991-98). Dalbec, who hit 26 home runs with the Sea Dogs, reached Boston last year and belted eight home runs in just 23 games. Only Xander Bogaerts and Rafael Devers had more (both 11), but with over twice as many at-bats. Dalbec homered in every 10 at-bats. To add to the hype, Dalbec leads the majors in home runs (seven) this spring.

C is for Closer. The position is not settled and that is unsettling. Both candidates, Matt Barnes and Adam Ottavino, have 0.00 ERAs this spring, but neither is an established closer. Barnes will not be available on Opening Day after testing positive for COVID-19. He has been placed on the restricted list and will remain out for at least 10 days. Look at Boston’s last four title runs, and there was a definitive closer – Keith Foulke (2004), Jonathan Papelbon (2007), Koji Uehara (2013) and Craig Kimbrel (2018), although Kimbrel faded in the playoffs.

D is for Deals. Chief Baseball Officer Chaim Bloom rebuilt Boston’s roster without the help of mega-salary signings. He found other ways, including some shrewd trades that obtained players, some major league ready (Ottavino, starter Nick Pivetta and outfielders Alex Verdugo and Franchy Cordero), some on the verge (infielder Jeter Downs and starter Connor Seabold, among others). Bloom got Pivetta and Seabold from Philadelphia for Brandon Workman and Heath Hembree, both of whom underperformed and were let go by the Phillies.

E for E-Rod, aka Eduardo Rodriguez. He was initially named the Opening Day starter, until he was shelved on Friday because of a dead arm. That could be understandable considering Rodriguez missed all of last year because of myocarditis. But it tempers the anticipation that this 2021 rotation was going to be much improved from the train wreck of 2020.

F is for Free Agents. George Springer (six years, $150 million), J.T. Realmuto (five years, $115 million) and Trevor Bauer (three, $102 million) signed elsewhere. Bloom went thrifty, signing infielder Kiké Hernández (two years, $14 million), starter Garrett Richards (one year, $10 million), outfielder Hunter Renfroe (one year, $3.1 million), utility player Marwin Gonzalez (one year, $3 million) and reliever Hirokazu Sawamura (two years, $3 million). Boston has a club option with Richards for 2022.

G is for Garretts. While Boston has hopes for Garrett Richards to return to pre-injury form, the Red Sox are thrilled with Rule 5 draft pick Garrett Whitlock, who was snagged from the Yankees. Normally, Rule 5 players are stashed on a major league roster with hopes of producing later. But Whitlock has shined this spring, striking out 12 in nine innings, allowing one run and no walks.

The Portland Sea Dogs have asked the state to allow 28 percent capacity – or about 2,000 fans – for games at Hadlock Field this season, to accommodate for social distancing. Ben McCanna/Staff Photographer

H for Hadlock Field. Last year, Portland’s beloved ballpark hosted golf and dining events, but there was no crack of the bat, no sound of balls popping into gloves. That changes on May 4 when the Portland Sea Dogs return to Hadlock.

I is for Infield. The signing of Hernández (and retirement of Dustin Pedroia) ended the speculation about second base, and Dalbec’s emergence ended ideas of platooning at first. Bogaerts enters his ninth season with Boston, and seventh as the full-time shortstop (deferring to Stephen Drew for parts of 2013-14). Devers is back at third, hoping for more consistency. He averages one error every five games.

J is for Julio. Did you know that is J.D. Martinez’s first name (Julio Daniel)? He is Boston’s experienced slugger, hoping to rebound from a down season (.213 batting average, seven home runs in 54 games).

K for Kids. Corner infielder Triston Casas, 21; center fielder Gilberto Jimenez, 20; and second baseman Nick Yorke, 18, were all invited to major league spring training. Boston is pushing these young talents, and it could be quite a gold rush in the coming years. Casas likely will begin this season in Portland. Jimenez could join him later, and who knows with Yorke, last year’s first-round draft pick.

L is for Ligament. The tricky elbow ligament that sometimes tears in a pitcher’s arm, requiring Tommy John surgery and a year-plus of rehab, is causing concern. Starters Chris Sale, Nathan Eovaldi and Richards have had the surgery. Sale is cautiously expected to return this summer. Pitching prospect Jay Groome missed most of 2018 and 2019 because of Tommy John surgery, and top pitching prospect Bryan Mata is hoping to avoid it after a recently diagnosed slight tear.

M is for “Mookie Who?” Wouldn’t it be nice for Boston fans be able to say that after a dismal season played in the shadows of the World Champion Los Angeles Dodgers and Mookie Betts, the star outfielder who Boston traded before he could hit the free-agent market. Betts is a great player, but Bloom needs to demonstrate Boston can be a winner without him.

Nathan Eovaldi is Boston’s No. 1 pitcher for now, with health concerns over Eduardo Rodriguez and with Chris Sale rehabbing from Tommy John surgery. Kathy Willens/Associated Press

N is for Nathan. With Sale on the shelf and doubts about Rodriguez, Nathan Eovaldi opens the season as Boston’s No. 1 starter. Slowed in the past by various injuries, Eovaldi and his health are key for the Red Sox.

O is for Outfield. From Aug. 2, 2016 to Feb. 9, 2020, the Red Sox could count on three outfielders. Just over a year later, Betts, Andrew Benintendi and Jackie Bradley Jr. are all gone. Verdugo has played one year in Boston, while Renfroe and Cordero are calling Fenway home for the first time.

P is for Potts, as in third baseman Hudson Potts. He is one of several prospects Bloom acquired to build up the farm system and who might play for the Sea Dogs. Potts and outfielder Jeisson Rosario came from San Diego in the Mitch Moreland trade. Others to look out for are catchers Ronaldo Hernandez and Connor Wong, and pitchers Frank German and Josh Winckowski.

Q is for Quality in the draft. Because of its dismal 2020 season, Boston has the fourth overall pick in the 2021 draft, their best positioning in 54 years (when Boston drafted pitcher Mike Garman with the third pick in 1967).

R is for Relievers. Building a dependable bullpen is risky business. Bloom has added arms, some already mentioned. Lefty Darwinzon Hernandez could break out if he improves his control (34 walks in 38 2/3 major league innings).

S is for Shift, which may be disappearing. Major League Baseball wants more offense, something that defensive shifts have hampered. MLB is experimenting this year with Double-A teams (including the Sea Dogs) not allowing infielders to position themselves in the outfield grass. The rule may expand later to mandate two infielders on each side of second base.

T is for Tanner. If Bloom had not built up the rotation depth, Tanner Houck may have been on the Opening Day roster. Houck might not be in the minors long if he continues his form from last year’s major league debut (three starts, three wins, 0.53 ERA).

U is for Underdog. Boston has risen rapidly from the ashes before, and this 2021 teams is said to have a similar feel as 2013, when the Red Sox went from worst to first; combining veterans who have won before with exciting young players.

Alex Verdugo put up his best numbers in the shortened 2020 season and might break through as an All-Star in 2021. Michael Dwyer/AssociatedPress

V is for Verdugo. Last year’s shortened season saw Alex Verdugo, 24, put up his best numbers (.308 batting average, .844 OPS). We may be looking at a 2021 All-Star.

W is for Worcester. The shuttle from Triple-A to Fenway is now 4 miles shorter, with Worcester, Massachusetts replacing Pawtucket, Rhode Island, as the Triple-A affiliate. The minors, now under MLB control, changed and contracted. There are no more short-season leagues (goodbye, Lowell Spinners) and Boston’s Class A affiliates switched levels, with Greenville, South Carolina, now in advanced A, and Salem, Virginia, now low A.

X is for Xander. Bogaerts, once a 19-year-old prospect in Portland in 2012, is now Boston’s leader in the clubhouse, combining a friendly personality with a determined drive for excellence.

Y is for Yankees. Boston can thank the Bombers for bullpen help (Ottavino and Whitlock). But New York remains the team’s chief rival (even if the Rays are defending American League champs and the Blue Jays are much improved), and sluggers Giancarlo Stanton and Aaron Judge are still to be feared.

Z is for Zeferjahn. Ryan Zeferjahn allows us to fill the last letter of this enjoyable exercise, but also point out the limbo of the 2020 season. Zeferjahn, 23, was a 2019 third-round draft pick of the Red Sox and made 12 starts for Lowell (31 strikeouts in 22 innings), but then had nowhere to play in 2020, with the minor league season canceled. Finally, Zeferjahn and others that were stuck, can get to playing again.

Baseball is back in 2021. Enjoy. It’s as easy as 1 2 3.