Nationals–Phillies rivalry

The Nationals–Phillies rivalry is a Major League Baseball rivalry between the Washington Nationals and the Philadelphia Phillies of the National League East division. The series was previously known as the Expos–Phillies rivalry when Nationals franchise was previously known as the Montreal Expos. The franchise relocated to Washington, D.C., in 2005. The two teams clashed frequently for control of the division during much of the 1980s and 1990s. The first postseason matchup between the two teams occurred during the 1981 National League Division Series, resulting in the Expos winning the series 3–2. The rivalry regrew in intensity following the Expos' relocation and rebranding given the proximity of Washington, D.C., and Philadelphia.

1970s
The Phillies were one of the original franchises in the National League, having formed in 1883. The league added two new franchises in 1969, one of which franchises was the Montreal Expos. Both teams struggled during the earlier half of the 1970s, with the Phillies failing to post a winning record between 1969 and 1974. The Expos fared much worse, failing to post a winning record in their first nine seasons. The two began to competitively clash during the 1979 season as the Expos managed two consecutive series sweeps of the Phillies, taking control of the division headed into June. The Phillies slowly fell out of contention for the division lead as the sweep by the Expos culminated in a six-game losing streak for Philadelphia, ultimately placing them third in the NL East by the end of the month. Things continued to spiral out of control for the Phillies as they lost five critical series matchups against the Dodgers, Cardinals, and Cubs, bringing them down to fourth in the division. The Expos experienced further success headed into September, with a 10-game win streak, and they held the division lead until a four-game skid allowed the Pittsburgh Pirates to win the division.

1980s
The following season saw the two teams battle throughout the duration of the season, all the way down to the final week before the end of the regular season. The Expos hosted the Phillies for the final three games of the season at Olympic Stadium with both teams tied for first. The Phillies took a close ten-inning victory in the first game of the series, clinching the division.

The 1981 season started with the Phillies running away with the division lead headed into June, four wins ahead of Montreal. The season then ground to a halt on June 12 due to a players' strike. Following the strike, Major League Baseball split the season into two halves. The Phillies won the first half and the Expos the second. The two teams then met in the divisional round resulting from the split-season format. The Expos won the first two games only to see the Phillies take games three and four. Game 5 saw Montreal prevail as Steve Rogers yielded six hits in a 3–0 Expos shutout victory.

1990s
Despite a rough start to the decade for both teams, the two found themselves embroiled in a heated race for the division title during the 1993 season. Montreal struggled through much of May, including two four-game sweeps at the hands of the San Francisco Giants and St Louis Cardinals. The Phillies, meanwhile, took an eight-game lead. Following the all-star break in July, Philadelphia stumbled, being swept by both the San Diego Padres and Houston Astros. The two teams met for their final matchup of the season with the Phillies leading by six games after the Expos endured a two-game series loss to the Houston Astros. During the first game in Montreal, Expos hearing-disabled rookie Curtis Pride doubled home two runners and scored on the following play during his first major league at-bat. After the game, Pride claimed he couldn't hear the ovation but he felt the vibration of the 45,757 Expos fans in attendance at Olympic Stadium. Despite the turnaround to the season, the Expos finished the season 94–68, three games behind the Phillies, and missed the posteason.

The following season, Montreal appeared to be on track to secure its first postseason berth since 1981, but the 1994–95 Major League Baseball strike ended any chances of a postseason run. The Expos then narrowly missed a divisional playoff berth in 1996. The Phillies also struggled near the end of the decade, failing to make the postseason from 1995 to 2001.

2000s
Both teams continued to struggle entering the new millennium, and budgetary issues began to severely affect the Expos' roster as several key stars were traded or lost to free agency. Philadelphia experienced a winning season in 2001, but missed a divisional berth by three games. 2002 and 2003 saw both teams struggle to appear in the postseason despite both managing several winning seasons but usually falling short as the Atlanta Braves often controlled much of the NL East.

Expos leave Montreal
Montreal's situation quickly devolved further in 2000. Budgetary issues heavily affected any free agency or postseason aspirations for the Expos after former owner Claude Brochu sold the team to American Businessman Jeffrey Loria in December 1999. Loria quickly damaged the team's relationship with the city and fans alike after demanding an increase in broadcast revenue and demanding a near-entirely public funded stadium in Downtown Montreal. Loria's management critically damaged the team financially, forcing the league to take control of the franchise and eventually relocate the team to Washington, D.C., for the 2005 season as the Washington Nationals. The Phillies hosted the Nationals on Opening Day on April 4, 2005; two days later, the Nationals beat the Phillies 7–3 for their first regular-season win following their relocation. The Nationals struggled for their first seven seasons in Washington, failing to appear in the postseason. The Phillies rebuilt their roster during the middle of the decade and won the 2008 World Series.

2010s
The Phillies attempted to capitalize on the success stemming from their 2008 World Series championship, but fell to the Yankees in the following year's World Series. The team stayed competitive, but fell short after an NLCS upset loss to the San Francisco Giants in 2010 and a divisional round loss to the St Louis Cardinals in 2011. Prior to the start of the 2012 campaign, the Nationals had endured several incidents of Philadelphia fans overtaking their home games during the series. Nationals management created the "Take Back the Park" campaign to heavily market to fans in surrounding areas to restrict the amount of visiting Phillies fans. Nationals management further banned ticket sales in Eastern Pennsylvania. The campaign proved successful as Nationals' home attendance grew substantially as the team qualified for the postseason, clinching the division title after back-to-back defeats of the Phillies in their final series of the season. The Nationals made four appearances in the divisional series between 2012 and 2017, but lost each time. Meanwhile, the Phillies did not post a winning season from 2012 to 2021.

Bryce Harper joins the Phillies
During the 2018 offseason, Nationals star right fielder (and 2015 National League MVP) Bryce Harper became a free agent. Harper had initially sought to renew his contract with Washington, but cited that he was displeased with the offers he received. After numerous reports had linked Harper to a $45 million annual contract with the Los Angeles Dodgers, he ultimately signed a 13-year, $330 million contract with the Phillies, then the second-largest contract in major league history. During his first press conference, Harper misspoke during his introductory speech, stating, "We want to bring a title back to D.C." Despite losing Harper, the Nationals won the 2019 World Series.

2020s
Despite the championship in 2019, the Nationals' roster was decimated by injuries and poor signings the following year. Longtime pitcher (and 2019 World Series MVP) Stephen Strasburg opted out of the remaining four years left on his contract, becoming a free agent. The Nationals re-signed him to a seven-year, $245 million contract, setting a record for any contract signed by a pitcher in league history. Strasburg then repeatedly battled injury from 2020 to 2022. Meanwhile, the Phillies reached the 2022 World Series but fell to the Houston Astros.