The Broncos returned to INVESCO Field at Mile High in Week 2 for their home-opener against the division rival Kansas City Chiefs. The game turned into another defensive battle, contrary to the typical shootouts the two teams usually have.  Not a single touchdown was scored by either team. The Broncos improved on their turnovers, however, with just 1 interception thrown by Jake Plummer, while the Chiefs gave up 2 fumbles. Tatum Bell and Mike Bell combined for 113 yards rushing, while Denver again gave up a 100-yard rusher, allowing Larry Johnson to rush for 126 yards. Neither quarterback was spectacular, both throwing for less than 200 yards. Javon Walker led all receivers with 79 yards. The game was tied 6-6 at the end of regulation, prompting an overtime in which a Jason Elam 39-yard field goal won the game for the Broncos. In 93 games between the two teams, it was both the first to never have a touchdown and also featured the lowest-ever score. It was also only the third time in franchise history that the Broncos did not commit a single penalty.
Question: What type of score led to the eventual win?
Answer: field goal