Tejada's two-run double in the sixth inning capped a three-run outburst that gave the Mets a 7-0 lead.
Daniel Murphy also contributed a two-run double for New York, which opened the year with a 3-0 record for the first time since 2007.
Jonathan Niese, who Saturday signed a five-year, $25.5 million contract, took a no-hitter into the seventh inning for the Mets. He finished by allowing four runs (two earned) on two hits, yielding four walks and striking out seven.
Frank Francisco fired a 1-2-3 ninth for his third save in three games.
Braves starter Mike Minor (0-1) was tagged for six runs on six hits over five innings.
Brian McCann homered and Justin Heyward drove in two runs for Atlanta.