Coming off their win over the Chargers, the Bills flew to Dolphin Stadium for a Week 8 AFC East duel with the Miami Dolphins.  In the first quarter, Buffalo trailed early as Dolphins QB Chad Pennington completed a 2-yard TD pass to TE Anthony Fasano.  The Bills responded with kicker Rian Lindell getting a 19-yard field goal.  In the second quarter, Buffalo took the lead as Lindell got a 43-yard and a 47-yard field goal. In the third quarter, the Bills increased their lead as RB Marshawn Lynch got an 8-yard TD run.  However, Miami began to respond as kicker Dan Carpenter got a 43-yard field goal, while RB Ricky Williams got a 3-yard TD run.  In the fourth quarter, the Dolphins sealed Buffalo's fate as Carpenter made a 45-yard field goal, LB Joey Porter causing QB Trent Edwards to fumble the ball in his own endzone (leading to a safety), and Carpenter nailing a 35-yard field goal.
Question: How many yards was the longest touchdown run?
Answer: 8