After holing up for two weeks with his college and pro scouts in preparation for free agency in March and the draft in April, Texans general manager Rick Smith will head to Indianapolis with members of his personnel department this week for the scouting combine. The combine begins Thursday and is followed by the start of free agency (March 12) and the draft (April 25-27). The Texans were $5.6 million under the salary cap last week. Their philosophy hasn’t changed. They plan to build through the draft, re-sign some of their free agents, extend contracts of key veterans like linebacker Brian Cushing and defensive end Antonio Smith, and fill in with inexpensive free agents. Forget about a possible trade with Minnesota for receiver Percy Harvin, who is threatening to hold out until he gets a new contract putting him among the highest-paid receivers. It also is not likely the Texans are going to spend millions on a veteran receiver who becomes unrestricted next month. Before free agency, though, Smith and coach Gary Kubiak have to worry about the combine and evaluating players they believe will fill specific needs. As the Texans approach the combine at Lucas Oil Stadium, it doesn’t take an expert to figure out their needs. They are looking for playmakers on both sides of the ball. Here’s an interesting statistic: In the Texans’ last four regular-season games, quarterback Matt Schaub threw one touchdown pass. During that same period, the defense intercepted one pass. Schaub threw two touchdown passes in the playoffs, and the defense intercepted one pass. Schaub needs a fast receiver who can stretch the defense to play opposite Andre Johnson. At this point in the evaluation process, the best receivers in the draft are Tennessee’s Cordarrelle Patterson, Baylor’s Terrance Williams, California’s Kevin Allen, Louisiana Tech’s Quinton Patton and West Virginia’s Tavon Austin.