Although he spent just one season with the team, 1967, Tommy Davis was a principal in 2 of the biggest trades the Mets made in their formative years, the one that brought him to the Mets and the one that sent him away.
Prior to the '67 season, the Mets sent two of their top players, Ron Hunt, the first genuine Mets all-star and arguably their most popular player and the talented but flawed regular center fielder Jim Hickman, to the Dodgers for one-time batting champ Tommy Davis and a promising young third baseman, Derrell Griffith.
Few Mets' fans lamented the loss of Hickman, but Hunt was another story. The general feeling was that the front office never appreciated Hunt as much as the fans did and felt he was easily replaceable at second base. Also, Davis was from Brooklyn and was probably expected to be a fan favorite. Davis was one of the premier hitters in the game, but after busting up his ankle sliding into second base, lost much of his speed and he became something of a liability in the field and on the bases. Still, there was no denying that the Mets never had a hitter with his capabilities and he turned in a solid season for the Mets, batting .302 with 16 home runs and 73 rbi's. Griffith was dealt away before he ever played for the Mets and never amounted to much, anyway. Hunt and Hickman still had some very productive years ahead of them, but primarily after both left the Dodgers.
As for Davis, after one season with the Mets, he was dealt in a package deal that brought the Mets Tommie Agee (the Mets also had to give up Jack Fisher, one of their better pitchers), who was of course, instrumental in the Mets' winning the 1969 World Series, but faded quickly after one more excellent season. Helped by the American League's adoption of the Designated Hitter rule, Davis racked up another 10 years in the major leagues after leaving the Mets. His reputation always was as a skilled line-drive hitter and one of the most proficient pinch-hitters around.
Having traded their regular centerfielder in the package for Davis, and seeing their new heralded centerfielder Don Bosch disappoint terribly, the Mets gave Cleon Jones the majority of playing time in center field in 1967. Flanked by Davis, and Ron Swoboda, this had to be one of the worst defensive outfields around, and thus the need for Agee. In the short run, of course, this trade worked out, although Davis ultimately had a better career than Agee. But while Agee was flashy and exciting, Davis was steady and reliable. Both good players. But while Agee has become a Mets hero for the ages, Davis' tenure with the team has been practically forgotten.