The Ravens were behind 6-3 in the second quarter when Smith picked off Houston's Matt Schaub and rambled 37 yards for a score, igniting a run of 17 unanswered Baltimore points.
Doss' 82-yard punt return capped the stretch as the Ravens (2-1) held Houston to just 102 yards of total offense in the second half.
Joe Flacco completed 16-of-24 passes for 171 yards and Justin Tucker was true on three field goals in the win.
Schaub ended up completing 25-of-35 passes en route to 194 yards and an interception for the Texans (2-1), who lost wide receiver Andre Johnson to a leg injury in the defeat.
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