In Week 2, the Titans played their first road game of the year against the San Diego Chargers.  From the get-go, the Titans trailed as opposing kicker Nate Kaeding kicked a 28-yard field goal in the first quarter.  Things only got worse in the second quarter, as San Diego unleashed their ultimate weapon, RB LaDainian Tomlinson, as he got a 4-yard and an 8-yard TD run and Kaeding got a 31-yard field goal to give Tennessee a 20-0 halftime deficit.  Things weren't any better in the third quarter, as Kaeding got a 35 and a 44-yard field goal for San Diego.  In the fourth quarter, the game was put well out of reach as opposing QB Philip Rivers completed a 12-yard TD pass to WR Vincent Jackson.  By this time, QB Kerry Collins was taken out and rookie QB Vince Young came in to complete an 18-yard pass to WR Drew Bennett.  However, the Chargers would deliver one more blow as opposing QB Charlie Whitehurst ran 14 yards for tha game's final TD.  With the loss, the Titans fell to 0-2.
Question: How many points did Tennessee trail by halftime?
Answer: 20