Coming off their last-second win over the Dolphins, the Texans continued their home stand with a Week 7 interconference duel with the winless Detroit Lions.  In the first quarter, Houston drew first blood as QB Matt Schaub completed a 2-yard TD pass to TE Owen Daniels, along with RB Ahman Green getting a 1-yard TD run.  In the second quarter, the Texans increased their lead as rookie RB Steve Slaton got a 1-yard TD run.  The Lions would respond with kicker Jason Hanson getting a 54-yard field goal. In the third quarter, Detroit tried to catch up as RB Kevin Smith got a 26-yard TD run.  Houston would answer with Schaub hooking up with Daniels again on a 1-yard TD pass.  In the fourth quarter, the Lions tried to rally as QB Dan Orlovsky completed a 96-yard TD pass to WR Calvin Johnson, along with Hanson nailing a 54-yard field goal.  Fortunately, the Texans' defense stiffened for the victory.

Based on the above article, answer a question. How many yards was the longest touchdown run?
26