Colts' improving defense faces tall task against Falcons

Tennessee Titans quarterback Marcus Mariota (8) avoids a tackle attempt by Indianapolis Colts outside linebacker Darius Leonard (53) during Indianapolis' 19-17 win over the Titans on Sunday, September 15, 2019, at Nissan Stadium. (Austin Anthony/Daily News via AP)

Atlanta Falcons wide receiver Julio Jones (11) makes a touchdown catch against Philadelphia Eagles cornerback Ronald Darby (21) during the second half of an NFL football game, Sunday, Sept. 15, 2019, in Atlanta. (AP Photo/John Amis)

Atlanta Falcons quarterback Matt Ryan (2) throws in the pocket against the Philadelphia Eagles during the second half of an NFL football game, Sunday, Sept. 15, 2019, in Atlanta. (AP Photo/John Amis)

Atlanta Falcons quarterback Matt Ryan (2) celebrates with wide receiver Julio Jones (11) who ran down the tunnel after his go-ahead and eventual game-winning touchdown reception against the Philadelphia Eagles in an NFL football game, Sunday, Sept. 15, 2019, in Atlanta. Atlanta won 24-20. (Curtis Compton/Atlanta Journal-Constitution via AP)

Tennessee Titans quarterback Marcus Mariota (8) flips as he is hit by Indianapolis Colts defenders including Clayton Geathers (26) and Pierre Desir (35) in the first half of an NFL football game Sunday, Sept. 15, 2019, in Nashville, Tenn. (AP Photo/James Kenney)

Indianapolis Colts cornerback Quincy Wilson (31) breaks up a pass intended for Tennessee Titans wide receiver A.J. Brown (11) to end the Titans' final drive in the final seconds of the fourth quarter of an NFL football game Sunday, Sept. 15, 2019, in Nashville, Tenn. (AP Photo/Wade Payne)