Kenny Rosenberg

Kenneth Walter Rosenberg (born July 9, 1995) is an American professional baseball pitcher who is a free agent. He has previously played in Major League Baseball (MLB) for the Los Angeles Angels and in the KBO League for the Kiwoom Heroes. He played college baseball at California State University, Northridge, and was drafted by the Tampa Bay Rays in the 8th round of the 2016 MLB draft. He made his MLB debut with the Angels in 2022.

Amateur career Rosenberg was born in Mill Valley, California, a small town north of San Francisco, later lived in Santa Clarita, California, and is Jewish. He attended Tamalpais High School, where he was an All-MCAL First Team pitcher and first baseman in baseball in 2013, as well as an All-League goalkeeper in soccer. As a senior, on the mound Rosenberg had 75 strikeouts in 49 innings, with two shutouts. He was named Big West Conference All-Academic Team.

In 2018, Rosenberg pitched for the Charlotte Stone Crabs of the Single–A Florida State League.

In 2019, Rosenberg pitched primarily for the Double-A Montgomery Biscuits, also pitching in one game for the Triple-A Durham Bulls. He went 11-4 with a 3.29 ERA in 25 games (16 starts) for Montgomery, and was named a midseason Southern League All Star. His aggregate 114 strikeouts were third among Rays minor leaguers.

The Rays invited Rosenberg to spring training in 2021. He split the 2021 season between the FCL Rays, Montgomery, and Durham, going a combined 4-1 with a 2.81 ERA and 59 strikeouts over innings (12.7 strikeouts per 9 innings).

Los Angeles Angels 2022 On December 8, 2021, Rosenberg was selected by the Los Angeles Angels with the 8th pick in the minor league phase of the 2021 Rule 5 draft.

Rosenberg opened the 2022 season with the Salt Lake Bees. On April 18, 2022, the Angels selected his contract and promoted him to the major leagues for the first time. He made his MLB debut that day, surrendering a run in relief against the Houston Astros while striking out two. The following day, the Angels optioned Rosenberg back to Salt Lake. Rosenberg was recalled by the Angels on May 31 and made his second career major league appearance that day, throwing 99 pitches in 5 innings of relief against the New York Yankees. On June 19, Rosenberg made his first career start, pitching scoreless innings against the Seattle Mariners. In 2022 with the Salt Lake Bees, he was 2-5 with a 3.16 ERA (tied for 9th in the PCL) in 14 games (13 starts) covering innings in which he struck out 60 batters.

On December 12, 2022, Rosenberg was designated for assignment following the signing of Justin Garza. He cleared waivers and was sent outright to Salt Lake on December 19.

2023 In 20 starts for Triple–A Salt Lake in 2023, he posted a 7–7 record and 4.95 ERA with 120 strikeouts (6th in the Pacific Coast League) in 100 innings of work (10.8 strikeouts per 9 innings; leading all pitchers who pitched 80 or more innings). On August 5, 2023, the Angels selected Rosenberg's contract, adding him to the major league roster.

With the Angels in 2023, Rosenberg was 2-2 with a 3.82 ERA, as in 33 innings he struck out 29 batters.

2024 Rosenberg was optioned to Triple–A Salt Lake to begin the 2024 season. With Salt Lake, he was 9-7 with a 4.21 ERA in 21 starts (one complete game; tying for league lead) covering innings.

Kiwoom Heroes On November 25, 2024, Rosenberg signed an $800,000 contract with the Kiwoom Heroes of the KBO League. He made 13 starts for Kiwoom, logging a 4-4 record and 3.23 ERA with 80 strikeouts across innings pitched. Rosenberg was replaced by Lachlan Wells in June after suffering a hip injury. He was later ruled out for the season, and was subsequently released by the team after C. C. Mercedes was signed on July 30, 2025.

On April 21, 2026, Rosenberg re-signed with the Heroes on a six-week, $50,000 contract as an injury replacement for Nathan Wiles. He signed a new six-week, $50,000 contract with the team on May 28. He became a free agent following his last appearance on June 20.