Armas was one of the top power hitters in the American League in the early 1980s. Twice he led the American League in home runs, and topped all of Major League Baseball in runs batted in during the 1984 season. Armas was prone to injuries and went on the disabled list twelve times during his major league career, missing 302 games.
Career
Pittsburgh Pirates
Armas debuted with the Pittsburgh Pirates' Gulf Coast League affiliate in 1971 just shy of his eighteenth birthday. He spent six seasons in their farm system, batting .270 with 69 home runs when he received a September call-up in 1976. He appeared in four games for the Pirates, and collected two hits in six at-bats.
Armas was the opening day right fielder for the A's in 1977, though by the end of the season, he was starting in center and saw most of his action there. Armas' inability to stay healthy limited him to just 91 games in 1978 and 80 in 1979. For 1980, Armas became a full-time right fielder, and finally played a full season, batting .279 with 35 home runs and 109 runs batted in in 158 games.
In Boston, Armas became the center fielder, sharing the outfield with Jim Rice (LF) and Dwight Evans (RF). Although he was booed by fans for his low batting average (.218), he placed second in the AL with 36 home runs and seventh with 107 RBI.
Armas had a monster 1984, batting .268 and leading the AL with 43 home runs, 123 RBI, 77 extra-base hits, and 339 total bases. He was named to The Sporting News and UPI postseason AL All-Star teams, was Boston's co-MVP, and placed seventh in AL MVP balloting.
From 1980 to 1985, Armas hit more homers (187) than any other AL player. His next two seasons were ruined by recurring leg injuries and Boston's acquisition of Dave Henderson. Armas was released after batting just once in the 1986 World Series. In the following years, he became a valuable role player for the Angels, and he retired after the 1989 season.
Twice he finished in the top ten in AL Most Valuable Player award balloting (4th, 1981; 7th, 1984).
California Angels
Armas was signed as a free agent by the California Angels In July 1987, and played 3 seasons with them (1987–1989) to finish out his Major League career. For his career playing in 1,432 games over 14 seasons, Armas tallied 251 home runs, 614 runs, 204 doubles, 39 triples, 815 RBI, and 1,302 hits.
His playing career in Venezuela was a stellar one. He started playing with the Leones and later joined the Caribes de Oriente. His 97 career home runs were the Venezuelan professional baseball record, before another center fielder—Robert Pérez "the black wall" of Cardenales de Lara—set a new mark in 2007. In addition, Armas is fourth in the all-time list of RBI leaders, with 412.