WATCH: Chiefs Ian Book Leads Scoring Drive, KC Still Falls to Bears 34-21

The Kansas City Chiefs came alive in the second half of their preseason finale against the Chicago Bears at GEHA Field at Arrowhead Stadium on Thursday night.

However, their offensive resurgence was a bit too late.

Facing a 34-14 fourth-quarter deficit, reserve quarterback Ian Book orchestrated his second scoring drive of the half — this time leading the Chiefs 63 yards on three plays. The drive was highlighted by a 49-yard completion from Book to receiver Montrell Washington. Book capped the drive by completing a 10-yard scoring strike to wideout Baylor Cupp, cutting Chicago’s lead to 34-21.

Unfortunately, the lack of time remaining on the clock became their ultimate enemy, as the Chiefs fell to the Bears by the same score.

The Chiefs are about to embark on a journey that they hope will lead them to heights no team in the modern NFL era has previously been — a Super Bowl championship three-peat. As a three-time Super Bowl Champion (including three Super Bowl MVPs,) two-time NFL MVP, and three-time All-Pro, quarterback Patrick Mahomes has already had the career about which most athletes can only dream.

At age 28, he is just entering the prime of his career. His top target, tight end Travis Kelce is a nine-time Pro Bowler and a seven-time All-Pro with four first-team nods. The Chiefs have also upgraded their vertical passing game by adding rookie speedster Xavier Worthy.

Related: WATCH: Chiefs Cut Bears Lead with Powell TD, Trail 34-14

Still, fans and media alike should give rightful credit to coordinator Steve Spagnoulo’s defense, whose blitz-heavy schemes have helped defensive tackle Chris Jones and cornerback Trent McDuffie thrive.

After Thursday night’s preseason finale, the Chiefs will next return to GEHA Field at Arrowhead Stadium to host the Baltimore Ravens on Sept. 5.