TAMPA — To prevent preseason wear on his three normal practice fields, new USF coach Charlie Strong is staging the first phase of the 2017 preseason on the fields used by the original Bulls two decades ago. If that's not throwback enough, he's trying to install another retro component: a defense with an edge. You know, the gritty, relentless Jim Leavitt units of yesteryear. Certainly not last year. "Defensively, we know that's got to be our biggest improvement," Strong said around dusk Monday, after the Bulls' first preseason workout. "We have to improve on defense, and we have to get better, and there's no reason for us not to." A potentially historic season, which undoubtedly will commence with USF being ranked and features a fringe Heisman candidate (senior Quinton Flowers) at quarterback, hinges on it. "Last year, we were kind of the weak link of the team," said fifth-year senior middle linebacker Auggie Sanchez, who nonetheless watched the Bulls (11-2) set a program record for wins. "I think this year we've got some expectations, we've got some guys that are ticked off at it, and they want to improve on what we did last year." As many as seven seniors could start for a unit that finished 120th nationally (482 ypg) in total defense and allowed nearly 200 rushing yards a game under former coordinator Raymond Woodie. Moreover, three players sidelined all or part of spring — Sanchez and ends Kirk Livingstone and Vincent Jackson — all practiced Monday. In fact, Strong said his entire depth chart entered camp healthy. He only wishes it featured a few more names on the defensive side, especially at linebacker. Sanchez, 65 tackles shy of becoming USF's all-time tackles leader, is the only linebacker on the depth chart who has started a college game, though sophomore Nico Sawtelle and junior Danny Thomas have played extensively as backups. Adding depth up front, especially in the interior, also is a priority, Strong said. "The secondary is solid because that's where your seniors are," Strong said. "But the linebacker position right now is where we've just got to find some depth." Contact Joey Knight at [email protected] Follow @TBTimes_Bulls.