Jasier Herrera Yánes
- Bats Right, Throws Right
- Height 6' 5", Weight 190 lb.
Herrera was signed by San Francisco Giants scout Daniel Mavarez in November 2014.  He was 0-2 with a 9.26 ERA for the 2015 DSL Giants, striking out 15 in 11 2/3 IP bur walking ten and throwing six wild pitches. He improved to 3-1, 3.27 with five saves for the same team the next year. He then had a setback, missing 2017 due to Tommy John surgery.  Returning to action with the 2018 AZL Giants Orange, he had a 1-4, 3.88 record.
The Cartagena native split 2019 between the AZL Giants Black (6-1, 1.99) and Salem-Keizer Volcanoes (3-1, 4.00). He was among the Arizona League leaders in ERA (3rd, behind Adolfo Ramirez and Gabe Morales), wins (tied for 3rd) and WHIP (1.12, 10th).  He tied Seth Corry, Matt Frisbee, Alfred Gutierrez and Aaron Phillips for the most wins by a Giants farmhand, despite not having played in a full-season league. The 2020 minor league season was wiped out by the COVID-19 pandemic.
Early in 2021, he pitched for Colombia in the 2020 Americas Olympic Qualifier (the Olympics and qualifiers had kept the 2020 moniker after COVID-19 delays despite being held in 2021). He pitched once, relieving Jean Ruiz in the 7th with a 2-0 deficit against Venezuela. He went 1-2-3 against Luis Castro, Ramón Flores and Hernán Pérez. In the 8th, he allowed a single to Alí Castillo but he was caught stealing. He then got Juniel Querecuto on a liner, walked Robinson Chirinos and retired Carlos Pérez. By the time Sergio Ocampo took over in the 9th, Colombia had tied it at two, but they still took the loss.  He split the summer between the Eugene Emeralds (1-2, 3.99 in 24 G) and Sacramento River Cats (3 R in 2 IP), making it to AAA for the first time at age 23. He was back with Colombia for the 2021 U-23 Baseball World Cup, allowing two runs in 3 2/3 IP (again facing Venezuela) as his team won the Bronze Medal.