Williams Alexander Jerez (Spanish pronunciation: [jeˈɾeθ] born May 16, 1992) is a Dominican professional baseball pitcher for the Guerreros de Oaxaca of the Mexican League.

[1] During his senior year he hit .692 with five home runs and 26 stolen bases, leading Grand Street to the 2011 Public Schools Athletic League (PSAL) Class A semi-finals.

[1] The Boston Red Sox selected Jerez in the second round of the 2011 MLB Draft, signing him with a bonus of $443,700.

[4][3] He made his debut with the Gulf Coast League Red Sox in 2012 and collected hits in 11 of 12 games during one early-season stretch, batting as high as .340, but eventually he tapered off.

[10] In 2012, Jerez started 32 games with the Short-Season A Lowell Spinners before missing the remainder of the season with hand injury.

In that season, he posted a 3–1 record with a 2.22 ERA and one save coming out of bullpen for the GCL Red Sox.

He then gained a promotion to High A Salem Red Sox and was more dominant, posting a 1–0 record with a 0.73 ERA and 12 strikeouts in 12 innings.

[10] The Portland Sea Dogs would be the fifth stop in just a year and a half for Jerez, as he collected scoreless outings in 13 of 22 appearances since his Double-A debut on June 24, 2015.

[12] He opened 2017 at Portland, where he went 2–0 with four saves and 3.10 ERA in 29 games before joining the Triple-A Pawtucket Red Sox in the month of August.

[15] On August 7, the Angels called up Jerez and he made his major league debut, pitching two scoreless innings against the Detroit Tigers.

[23] On April 20, 2022, Jerez signed with the Staten Island FerryHawks of the Atlantic League of Professional Baseball.

[24] Jerez made 6 appearances for the FerryHawks, struggling to an 0-2 record and 19.29 ERA with 4 strikeouts in 4+2⁄3 innings pitched.

On April 7, 2023, Jerez signed with the Charleston Dirty Birds of the Atlantic League of Professional Baseball.