Welch, 24, spent the last 2 seasons with the Brooklyn Cyclones after making his professional debut in 2012 with the Kingsport Mets and splitting the 2013 season between the K-Mets and the Gulf Coast League Mets. The right-handed pitcher owns a 4-2 record with a 4.13 ERA in 27 games, 6 starts, with the Mets organization earning a 4.13 ERA over 65 1/3 innings pitched.
Valdez, 25, made his professional debut in 2008 with the Dominican Summer League Angels before being released. The Mets signed him in 2011 and he spent that season in the Dominican Summer League again. In 2012 he pitched for the Kingsport Mets before earning a promotion to the Brooklyn Cyclones in 2013. He spent the last 3 seasons with the Brooklyn Cyclones, with an addition 7 games with the Savannah Sand Gnats of the South Atlantic League. In 68 professional games he has 25 starts and earned a 7-10 record and a 3.44 ERA over 167 1/3 innings. He struck out a 139 batters while walking 73.
Celas, 24, has been with the Mets organization since 2010. After spending his first 3 seasons with the Dominican Summer League Mets he made his United States debut in 2013 with the Gulf Coast League Mets. Jose pitched for the GCL Mets for the 2013 and 2014 seasons before pitching for the Brooklyn Cyclones in 2015. He owns a career 6-7 record with a 4.15 ERA over 39 games, 19 starts. In 112 2/3 innings pitched he struck out 96 batters and walked 83.