Aaron Judge on Thursday blasted the first home run of the Major League Baseball (MLB) season, sparking the New York Yankees to victory to kick off the 2023 campaign with new rules and familiar feats.

The 30-year-old American outfielder, in his first time at bat since being named captain of the historic MLB club, smashed the second pitch he saw from San Francisco right-hander Logan Webb over the centrefield wall for a solo homer in the first inning to start the scoring in New York's 5-0 triumph.

Fans at Yankee Stadium chanted "M-V-P" as Judge, last year's American League (AL) Most Valuable Player, walked to home plate and picked up right where he left off in 2022.

Judge belted 62 homers last year to break the the AL single-season homer record of 61 set by Yankees legend Roger Maris in 1961.

Judge was courted by several teams as a free agent in the off-season, including San Francisco, but signed an MLB record free agent deal for nine years at US$360 million last December to stay with New York.

New York's Gleyber Torres blasted a two-run homer in the fourth and right-handed pitcher Gerrit Cole struck out 11 over six shutout innings while allowing only three hits with two walks to earn the victory.

At Washington, Atlanta's Travis d'Arnaud went 4-for-5 at the plate, scoring twice and driving in two more runs in the Braves' 7-2 rout in the National League season opener.

Braves pitcher Collin McHugh ran afoul of the new time clock in the eighth inning when he was issued a ball against Washington batter Jeimer Candelario, who walked. McHugh pleaded his case to the umpire to no avail.

Two of the oldest and most storied venues in baseball, Boston's Fenway Park and Chicago's Wrigley Field, also hosted early openers.

Marcus Stroman struck out eight and allowed only three hits over six shutout innings to spark the Chicago Cubs over visiting Milwaukee 4-0.

Dansby Swanson hit a two-run single in the third inning and scored on a Trey Mancini single while Ian Happ scored on a fielder's choice to provide all the scoring the Cubs needed.

At Boston, Baltimore's Adley Rutschman went 5-for-5 with a solo homer in the first inning and four runs batted in while Ramon Urias added a two-run homer off Red Sox starter Corey Kluber in the Orioles' 10-9 triumph.

All 30 MLB clubs were in action on opening day, which marked the debut of new rules aimed at hastening the pace of play. Pre-season contests were reduced by an average of 26 minutes to two hours and 35 minutes.

A new pitch clock will limit the amount of time pitchers have to engage with batters while defenders will be limited in how far they will be able to shift out of typical positions to try and better field batters based on past hitting charts.

The size of bases was also increased, creating a bigger target for base stealers who will face less targeting for pickoff throws from pitchers under tighter restrictions.

Braves pitcher Collin McHugh ran afoul of the new time clock in the eighth inning when he was issued a ball against Washington batter Jeimer Candelario, who walked. McHugh pleaded his case to the umpire to no avail.

Chicago's Stroman also was called for a pitch clock violation, taking too long to deliver a pitch to Milwaukee's Christian Yelich.

One pitcher who will not have to worry about the new rules for a while longer is Justin Verlander of the New York Mets.

Verlander, last year's AL Cy Young Award winner as top pitcher after helping the Houston Astros to a World Series crown, signed a two-year deal worth US$86.6 million with the Mets.

But the 40-year-old right-hander was put on the MLB injured list on Thursday with a strained muscle near his pitching shoulder.

Verlander will miss his scheduled Saturday start at Miami and be re-evaluated next week, the Mets said. (AFP)