After a tough home loss, the Steelers traveled down south again to take on the Jaguars.  The Jags scored first as Josh Scobee kicked a 43-yard field goal for a 3-0 lead for the only score of the first quarter.  The Steelers answered to tie the game when Shaun Suisham kicked a 24-yard field goal for a 3-3 game.  They eventually took the lead when Ben Roetlisberger found Michael Palmer on a 1-yard TD pass to take a 10-3 lead.  The Jags pulled within 4 before halftime when Scobee nailed a 35-yard field goal to make it a 10-6 game.  In the 3rd quarter, the Jags came within a point as Scobee kicked a 36-yard field goal to make it a 10-9 game for the only score of the quarter.  In the 4th quarter however, Brice McCain picked off Jags QB Blake Bortles and returned the interception for a 22-yard TD increasing their lead to the eventual final score of 17-9.
Question: How many points did the Jaguars trail by at halftime?
Answer: 4