Thanks to the New England Patriots (yeah, how strange is that?), the Indianapolis Colts control their own destiny for an improbable AFC South division title. All they have to do is win their last three games. Two of those games are against AFC South rival Houston. The Colts (9-4) travel to Houston to take on the Texans (11-2) at 1 p.m. Sunday. Here are five pivotal factors if the Colts are to get that next necessary win:How are they going to keep Texans defensive end J.J. Watt away from quarterback Andrew Luck? It's a necessity, but it seems almost impossible. Watt has 16.5 sacks and 15 passes defended this season, making him only the second player to record at least 13 of each since 1991. The other player: the legendary Reggie White. It'll be up to the Colts' offensive line to keep him away from Luck. Advice for Luck: When you see Watt in the corner of your eye – run, man, run!Luck knows it. The Colts coaching staff knows it. The Texans know it. The rookie quarterback has a tendency to throw interceptions, mostly on the road. Luck has a league-high 18 picks (tied with Drew Brees), and 13 of them have come on the road. Maybe it's the noise. Maybe it's playing from behind. Maybe it's the added pressure that teams find with their home fans pumping the adrenalin. Whatever it is, Luck needs to limit those picks. The Colts are 7-1 when Luck throws one or zero interceptions. That's not coincidence.Luck's offense will be helped immensely if running back Vick Ballard can generate some yardage on the ground, keeping the Texans honest in their defense. This needs to happen early, too. Ballard rushed for a career-high 94 yards last week. Here's the problem in Houston: The Texans rank second in the NFL in rushing defense, allowing only 90.8 yards per game.The Colts now have two cornerbacks who have been the AFC Defensive Player of the Week in Darius Butler and Cassius Vaughn. No one could have predicted the previous sentence would exist when they joined the lineup. Their reward is the fact they have to find some way to slow Andre Johnson, who ranks fourth in receiving yardage (1,209), just behind the Colts' Reggie Wayne (1,220). Incidentally, Johnson is on pace to become the second-fastest to reach 800 career receptions. The first: Colts great Marvin Harrison.Arian Foster's career took off in 2010 when he ran for 231 yards and three touchdowns in a win over the Colts. Since then, he's become one of the league's best. In three career games against the Colts, he has 491 yards (6.9 per carry) and five touchdowns. So they'll probably have to slow him somehow, the way they limited the Titans' Chris Johnson last week. Of course, that's much easier said than done.