By Dan Lyons The Titans may be without their starter for the remainder of the year. Titans quarterback Ryan Tannehill underwent surgery on his ankle this week and will not play again during the regular season, as the team looks to stay in the playoff hunt, ESPN’s Adam Schefter reports. As Tennessee (7–7) fights for a playoff spot, it may have to rely on rookie quarterback Malik Willis to guide it there. If the team manages to hold onto its lead in the AFC South, Tannehill is still “unlikely” to return in the postseason, per Schefter. Tannehill went down last Sunday after taking a hit from Char…