Teng, 27, spent parts of the 2024 and 2025 seasons with the Giants at the major league level. Across those two seasons, he appeared in 12 games, including seven starts, compiling a 2–4 record with a 7.30 ERA over 40.2 innings.

Teng made eight appearances in 2025, seven of them starts, and logged 29.2 innings. He struck out 39 batters during that span, translating to 11.8 strikeouts per nine innings.

According to Chandler Rome of The Athletic, the Astros are sending catching prospect Jancel Villareal to San Francisco in the deal.

Teng is considered an optionable swingman, capable of pitching either as a starter or in relief, giving Houston added flexibility as it looks to bolster its right-handed pitching depth.

While his run prevention remained a challenge in 2025, Teng showed measurable improvement compared to his rookie season. Opponents hit .254 against him last year, down from .326 in 2024, and his opponents’ OPS dropped from .936 to .732. His control also improved, as reflected by a 2.3 strikeout-to-walk ratio after issuing nearly as many walks as strikeouts the year before.

Teng allowed 21 earned runs in 2025 and finished the season with a 6.37 ERA. For his career, he has surrendered four home runs and holds a 1.70 WHIP.

The trade is the latest in a series of transactions for the Astros as the club continues to adjust its roster entering the final stretch of the offseason.