Baseball’s opening weekend featured spectacular plays, dominant pitching and long-anticipated player debuts. And after an offseason where experts predicted the American League to maintain a stranglehold on baseball’s upper crust, it was National League powers who impressed.

One of the biggest stories this offseason was star outfielder Bryce Harper choosing to sign a 13-year, $330 million contract with the Philadelphia Phillies. Harper left his mark in Philadelphia’s opening series with the Atlanta Braves. The first hit for his new club was a 465-foot home run on Friday afternoon. He also hit a home run in Sunday’s game against the Braves, fueling the Phillies to a three-game sweep of the reigning division champions.

National League Central playoff contenders collided in Milwaukee as the Brewers and the Cardinals lived up to its billing and provided some great moments.

In game one, Brewers outfielder Lorenzo Cain robbed Cardinals first baseman Jose Martinez of a game-winning home run in the ninth inning. Brewers outfielder and 2018 NL MVP Christian Yelich is off to a historic pace in the young season, homering in his first four games. Yelich is only the sixth player ever to do that. His final hit of the series was a walk-off two-run double to win the series for the Brewers, three games to one.

But the biggest shock this weekend came between the Baltimore Orioles and the New York Yankees. The Orioles surprised everyone by winning the series 2-1 at Yankee Stadium. Considering how both teams played last season, with the Orioles winning a meager 47 games to the Yankees’ 100, it was expected that the Yankees would at least win the series and probably sweep at home.

While the Yankees did lose the series, they saw five time All-Star shortstop Troy Tulowitzki get his first hit since 2017 after spending a large part of the last two seasons on the injured list. In the same game, Tulowitzki also hit his first home run in almost two years.

The Chicago Cubs and Texas Rangers played the only interleague series of the weekend and featured the return of Cubs pitcher Yu Darvish back to the starting rotation. Darvish sat out most of last season after suffering an elbow injury in May.

Darvish was shaky in his return on Saturday, pitching only for a career-low 2.2 innings, throwing 75 pitches, walking seven batters and giving up three runs.

The third and final game of the series saw both teams explode for a combined 21 runs and 28 hits. Texas secured a walk-off win on a ninth-inning wild pitch and captured the series 2-1.

The reigning world champion Boston Red Sox opened 2019 in ugly fashion against the Seattle Mariners. Boston’s pitching staff allowed six runs or more in each of its four games in Seattle and won only once.

Despite the bad series, the Red Sox front office managed to solidify its shortstop of the future, Xander Bogaerts, to a six-year, $132 million contract extension.

The San Diego Padres unveiled a revamped lineup this weekend. The Padres broke in two new signings at the corner infield spots in first baseman Eric Hosmer and third baseman Manny Machado, who signed for eight years, $144 million, and 10 years, $300 million, respectively.

In addition to Hosmer and Machado, three highly rated rookies made their debuts. The most anticipated was shortstop Fernando Tatis Jr., the No. 2 prospect in baseball entering this season. Tatis did not disappoint, picking up two hits in his debut.

Then on Saturday, rookie pitcher Nick Margevicius who, despite striking out five and surrendering only one run on three hits in five innings, earned a loss in his first major league start.

The last of the Padres’ notable weekend debuts belonged to starting pitcher Chris Paddack, who retired the first 10 batters he faced as part of a strong, five-inning, seven-strikeout showing. The Padres won 3-1 that afternoon, their third win of the four-game series with the San Francisco Giants.

The Toronto Blue Jays also debuted two rookies over the weekend against the Detroit Tigers. The first was starting pitcher Taylor Thornton, who struck out a team-record eight batters in a major league debut over five innings and only two hits.  

Elvis Luciano, another Toronto rookie, didn’t only make his debut, but history as well. He is now the youngest player in team history to make their debut and the only player in MLB history born in the year 2000. He surrendered only one hit over 1.1 innings of work in a 4-3 loss on Sunday.

The New York Mets started strong in Washington against the Nationals, especially at the plate. The Mets offense scored 18 runs in three games against All-Star starting pitchers Stephen Strasburg, and Patrick Corbin and Max Scherzer.

Mets rookie Pete Alonso, the top-ranked first baseman prospect by MLB Pipeline, was a major contributor to that offensive outburst. Alonso batted .500 in his first MLB series and drove in two runs. His six runs scored are now tied for the most through three games in franchise history.

The 2018 NL championship-winning Los Angeles Dodgers opened their 2019 campaign with a wholloping of the Arizona Diamondbacks. The Dodgers scored 42 runs over four games and hit 14 home runs. The eight they hit on Opening Day are an MLB record.

Finally, the Pittsburgh Pirates took on the Cincinnati Reds this weekend, splitting the first two games. In both games, the Pirates had dominant starting pitching performances. Game one saw Jameson Taillon allow only one run in his first six innings, before imploding in the seventh. The Reds scored four that inning en route to a 5-3 win.

Pitcher Trevor Williams started game two and threw six scoreless innings while striking out six. Williams owns a 1.20 ERA over his last 14 starts dating back to last season.

The first weekend of regular-season baseball rarely is able to accurately forecast the marathon season yet to be played. But for now, National League powers in Philadelphia and Los Angeles are flexing their muscles, while the American League’s elite struggle to find their footing.