The San Francisco Giants made a subtle but meaningful roster move on January 29, 2026, trading right-handed pitcher Kai-Wei Teng to the Houston Astros in exchange for minor-league catcher Jancel Villarroel and international bonus slot money.

Teng, 27, has spent parts of the last two seasons bouncing between Triple-A Sacramento and the big-league roster for the San Francisco Giants.

In his MLB career, he appeared in 12 games, seven of them starts, posting a 7.30 ERA across 40.2 innings.

See where C/OF Jancel Villarroel lands on the #SFGiants‘ Top 30 Prospects list after being acquired in the deal for Kai-Wei Teng: https://t.co/NfevKsouIP pic.twitter.com/Jc5R2HI8l9

— MLB Pipeline (@MLBPipeline) January 30, 2026

While the run prevention never fully stabilized, the raw stuff showed up. Teng struck out 46 hitters, including 39 punchouts in just 29.2 innings during the 2025 season, good for an eye-catching strikeout rate north of 11 per nine innings. Command issues — 25 walks at the major-league level — ultimately kept him from carving out a consistent role, but the arm talent remains real.

In return, the San Francisco Giants add 21-year-old Jancel Villarroel, a switch-hitting catcher with athleticism and speed.

During the 2025 season between Single-A and High-A, Villarroel hit .259 with a .351 on-base percentage and a .388 slugging percentage. He finished the year with eight home runs, 54 RBIs, and an impressive 20 stolen bases in 371 plate appearances — production that stands out for a player who primarily catches. Villarroel has also logged time at multiple defensive positions, adding to his versatility.

The international slot money gives the San Francisco Giants added flexibility on the global market, while Villarroel provides a developmental piece with upside. In the end, this move reflects a familiar Giants approach: converting short-term pitching depth into longer-term organizational value while keeping future options open.

More San Francisco Giants content from Sactown Sports

The San Francisco Giants have made some moves this offseason, but there is still plenty of time until the Opening Day festivities begin.

San Francisco has inked pitchers Adrian Houser and Tyler Mahle to free agent deals this winter, and this week’s signing of Gold Glove Award-winning center fielder Harrison Bader seemingly put the finishing touches on the offseason–or did it?

While the Giants aren’t expected to go big-fish hunting for the remaining top arms on the free agent market, like lefty Framber Valdez or right-hander Zach Gallen, they could bring in one of the many remaining veteran pitchers who are available and will command less financial commitments.

Could the SF Giants land one of these remaining free agent starters?

Upcoming San Francisco Giants & MLB Offseason Schedule

Early-January – MLB Arbitration Negotiations
Mid-February – Pitchers & Catchers report for Spring Training
Saturday, February 21st – @ Seattle Mariners (Spring Training Opener)
Wednesday, March 25th – vs. New York Yankees – 5:05 PM PT (Opening Day)

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