A left-handed pitcher, Righetti played in Major League Baseball from 1979 through 1995 for the New York Yankees, San Francisco Giants, Oakland Athletics, Toronto Blue Jays, and Chicago White Sox.

As a closer, he was twice named the AL Rolaids Relief Man of the Year and pitched in two MLB All-Star Games.

Paddy Cottrell, a scout for the Texas Rangers of Major League Baseball, noticed Righetti and suggested he become a pitcher due to his throwing motion.

[4] Righetti enrolled at San Jose City College, where he continued his development as a pitcher on the school's baseball team.

[citation needed] At Cottrell's urging, the Rangers selected Righetti on January 11, 1977, in the first round (10th overall pick) of the amateur draft.

[3] On November 10, 1978, the Yankees acquired Righetti, along with Juan Beníquez, Mike Griffin, Greg Jemison, and Paul Mirabella, while the Rangers acquired Sparky Lyle, Domingo Ramos, Mike Heath, Larry McCall, Dave Rajsich, and cash.

[8] Righetti made his major league debut with the Yankees on September 16, 1979, wearing uniform number 56.

In this game against the Detroit Tigers he pitched five innings, striking out three and allowing three hits, six walks, and three earned runs.

[7] However, Righetti struggled with his control, and spent the 1980 season with the Columbus Clippers of the Class AAA International League, where he had a 6–10 win–loss record and a 4.63 ERA with 101 walks and 139 strikeouts in 142 innings.

[9] Though Righetti pitched well in spring training in 1981, the Yankees did not have room for him on their roster, so he began the season with Columbus.

[7] Righetti won the American League's Rookie of the Year award, beating Rich Gedman and Bob Ojeda.

[13] Working with Ellis, Righetti made four starts for the Clippers, recording 33 strikeouts in 26 innings, before he was recalled to New York.

Twenty-five years later, Righetti reminisced about the game: My biggest worry, because I had a tendency to fall toward third base, was him (Boggs) tapping a ball between me and Mattingly and me trying to get to first base...I threw a lot of fastballs during the at bat, but the last slider I ended up throwing, he happened to miss it.

[14] In 1984 Righetti was moved to the Yankees' bullpen to replace Goose Gossage, who signed with the San Diego Padres in the offseason, as their closer.

[15] He proved even more effective in relief, averaging 32 saves per season over the next seven years with the Yankees, and being named an All-Star in 1986 and 1987.

[19] Righetti became concerned with the direction the Yankees were taking, as they had traded away Rickey Henderson, Jack Clark, and Dave Winfield.

After the 1990 season, Righetti signed as a free agent with the San Francisco Giants, receiving a four-year contract worth $10 million.

An analysis by Fangraphs showed that Righetti has an uncanny knack for teaching pitchers to avoid giving up home runs.