Andrew Luck threw for 285 yards and three touchdowns Sunday night as the Indianapolis Colts claimed the AFC’s final playoff spot with a 33-17 win over the Tennessee Titans at Nissan Stadium in Nashville.Luck, who completed 24 of 35 passes, finished the regular season with 38 touchdown passes, the most for a player who missed the previous season. He also enabled Indianapolis (10-6) to cap a comeback from a 1-5 start and earn a trip to AFC South champion Houston for a wild-card round game on Saturday.Tennessee (9-7) snapped a nine-year playoff drought last year with a home win over Jacksonville in Week 17, but wasn’t able to repeat the feat this time. The short-handed Titans played without quarterback Marcus Mariota (plantar fascia) and Pro Bowl defensive tackle Jurrell Casey (knee), and their absences were clearly felt.Blaine Gabbert replaced Mariota and threw for 165 yards on 18 of 29 passing, but also tossed two interceptions. The first was to Kenny Moore, kneecapping a promising drive near midfield with 9:05 remaining in the game.The Colts cashed it in with a 25-yard field goal by Adam Vinatieri with 3:55 left to give them a two-score cushion. Marlon Mack tacked on an 8-yard touchdown run with 2:24 remaining.Casey’s injury left a massive gap in the interior defense that Indianapolis exploited with consistency. Besides Luck’s passing, the Colts also pounded out 158 yards on 36 carries, enabling them to possess the ball for more than 40 minutes.