The blast off Fogg (0-1) with one out capped a 4-for-6 night for Tejada in which he drove in all three Houston runs and recorded his sixth career walk-off homer.
Houston rallied from a 2-0 deficit to send the game into extra innings. Colorado put up two runs in the fourth on back-to-back doubles by Todd Helton and Brad Hawpe that made it 1-0, followed by an RBI single by Smith.
But Houston cut the Rockies' lead to 2-1 in the fifth inning when Bourn doubled with two outs and then raced home on a hard shot by Tejada off the glove of shortstop Omar Quintanilla.
Tejada tied the game in the bottom of the ninth with a looping single to right that brought in Ivan Rodriguez from third.