In Week 14, the Titans traveled to Reliant Stadium for an AFC South rematch with the Houston Texans in a homecoming for QB Vince Young. The Titans struck first, notching 6 points on two field goals by kicker Rob Bironas.  The Texans scored next, however, when RB Ron Dayne plunged into the endzone from one-yard out for his first TD as a Texan. Dayne found the endzone again in the third quarter on a two-yard run to expand the lead to 8 points.  Late in the same quarter, RB Travis Henry added his own rushing score and the Titans  pulled to within one.  Following a Young interception by CB Demarcus Faggins, kicker Kris Brown connected on a 49-yarder. Tennessee would recapture the lead on Henry's second score, but Brown would tie the game with a 46 yarder forcing overtime. The Titans won the coin toss in overtime, and Young would end the game in dramatic fashion running for a 39-yard TD on a 3rd-and-14 early in the extra period.  The Titans improved to 6-7 and remained mathematically eligible for a wildcard playoff berth.
Question: How many yards was the longest touchdown run?
Answer: 39