A native of the Bronx, New York City, Lopez attended Cardinal Hayes High School.[2] He stood 6'1" and was cut from the basketball team in both his junior and senior years.[2] His uncle encouraged him to stick with it, and Lopez wound up attending Garden City Community College in Garden City, Kansas, where he redshirted his freshman season.[2] Lopez then transferred to Westchester Community College back in New York and played one year there. Between a huge growth spurt that saw him reach 6'7" and him "catching up" to his new physique, Lopez dominated competition.[2] At the national junior college tournament, scouts from many NCAA Division I programs attended to check out Lopez.[2] He chose to play for Fordham University, which was located 20 blocks away from his childhood home and was also the first NCAA program to express interest in him.[2] By the time he suited up for Fordham he stood 6'9" and weighed 240 pounds.[2]
Lopez began his collegiate career with the Fordham Rams as a redshirt sophomore in 1988–89.[2][3] That year he averaged 5.5 points, 5.8 rebounds, and 2.4 blocks per game.[3] The following season, Lopez increased his averages to 11.4 points, 10.3 rebounds, and 2.8 blocks, while also grabbing 1.6 steals a game.[3] The Rams finished in third place in the Metro Atlantic Athletic Conference (MAAC) North Division with a 10–6 conference record, and Lopez was named to the All-MAAC Second Team.[4][5]
Fordham left the MAAC prior to the start of Lopez's senior year in 1990–91 to join the Patriot League, which had formed in 1986.[6] He started 32 of 33 games (both career highs) and averaged 17.7 points, 9.5 rebounds, 3.0 blocks, and 2.0 steals per game.[3] He tied his own school single-game blocks record of 10, set the single-season blocks record of 100, and set the career record of 252 blocks in just three seasons played (since surpassed by Bryant Dunston, who played four years).[3] Fordham went 11–1 in Patriot League games, were crowned regular season champions, and went on to win the 1991 Patriot League tournament where Lopez was named the tournament MVP.[6][7] He was named to the All-Patriot League First Team and won the Patriot League Player of the Year award, which was the first time it was awarded in league history.[5] In 2008, Lopez was inducted into Fordham's Athletics Hall of Fame, and in 2015 he was honored on the Patriot League Men's Basketball 25th Anniversary Team.[5][8]
Following college, Lopez went undrafted in the 1991 NBA draft.[5] He had tryouts for the Portland Trail Blazers and Denver Nuggets but was never signed, so he instead played professionally in various international countries for the next eight years.[5][6] He also had a stint playing in the United States Basketball League before retiring.[5]