his major league debut. The Yankees erected a plaque for Robinson. Players active at the time of the number's retirement in 1997 were granted a special exemption permitting them to continue wearing the number for the remainder of their careers; the last such active player to wear No. 42 was Yankee relief pitcher Mariano Rivera. When Red Ruffing's plaque was dedicated in 2004, his son called it "the second-greatest honor you can have in baseball, in my opinion" trailing only induction into the National Baseball Hall of Fame. In addition to baseball related recognitions, the Knights of Columbus donated plaques in honor of the Masses celebrated at Yankee Stadium by Pope Paul VI on October 4, 1965, Pope John Paul II on October 2, 1979, and Pope Benedict XVI on April 20, 2008. The Yankees also dedicated a monument to the victims and rescue workers of the September 11 attacks on September 11, 2002, the first anniversary of the attacks. Monument Park II When the Yankees moved into the new Yankee Stadium after the 2008 season, the Yankees established a new Monument Park behind the fence in straightaway center field, below the Center Field Sports Bar that serves as the batter's eye. Built of pearl blue granite from Finland, this new monument park features the five Yankee monuments in a central area around a black marble Yankees logo. This is flanked by two short stone walls which hold the retired numbers. The plaques are mounted on the back wall and the September 11 monument is on one end of the park. In contrast to the old stadium, the new Monument Park is not readily visible from the field, and its relatively drab appearance and inconspicuous placement have led some to derisively nickname it "Monument Cave". Spectators can visit Monument Park prior to the beginning of each game. It closes 45 minutes before first pitch. The Yankees honored Rivera by retiring his uniform number on September 22, 2013, during his final season, making him the first active player to be enshrined in Monument Park. Mantle wore his No. 7 when he coached the Yankees in 1970, even though it was retired the previous year, while Berra wore his No. 8 while he coached the Yankees from 1976 through 1985, though it was retired in 1972. Similarly, when Martin returned to manage the Yankees in 1988, he wore his No. 1, which