The Eagles joined the NFL as an expansion team in 1933, but struggled over the course of their first decade, enduring repeated losing seasons. In 1943, when manpower shortages stemming from World War II made it impossible to fill the roster, the team temporarily merged with the Pittsburgh Steelers to form a team known as "the Phil-Pitt Steagles." (The merger, never intended as a permanent arrangement, was dissolved at the end of the 1943 season.) By the late 1940s, head coach Earle "Greasy" Neale and running back Steve Van Buren led the team to three consecutive NFL Championship Games, winning two of them in 1948 and 1949. Those two Championships mark the Eagles as the only NFL team ever to win back to back Championships by shutouts, defeating the Chicago Cardinals 7-0 in 1948 and the Los Angeles Rams 14-0 in 1949. The Eagles won their third NFL championship in 1960 under the leadership of future Pro Football Hall of Famers Norm Van Brocklin and Chuck Bednarik; the head coach was Buck Shaw. The 1960 Eagles, by a score of 17-13, became the only team to defeat Vince Lombardi and his Packers in the playoffs. Since the AFL-NFL merger, the Eagles have made it to two Super Bowls, 1980 and 2004, losing both.