The Mets announced the moves Saturday night, ensuring Syndergaard won’t return to the rotation until at least June as he comes back following Tommy John surgery last March.
Walker’s deal also includes a player option for 2023.
The 28-year-old Walker joins a rotation headed by two-time Cy Young Award winner Jacob deGrom. New York’s need for a pitcher increased with the loss of Seth Lugo, who will miss the start of the season following elbow surgery Tuesday to remove a bone spur.
New owner Steven Cohen has displayed a willingness to spend, retaining Marcus Stroman with an $18.9 million qualifying offer and acquiring Carlos Carrasco from Cleveland in a trade along with All-Star shortstop Francisco Lindor for a rotation also projected to include David Peterson.
Walker has a five-pitch repertoire with a 93 mph fastball mixed among sliders, split-finger fastballs, sinkers and curveballs.
He was 4-3 with a 2.70 ERA over 11 starts during the pandemic-shortened season for Seattle and Toronto, which acquired him Aug. 27 for a player to be named, who became outfielder prospect Alberto Rodriguez.