In these days before the exhibition games, the Detroit Tigers do almost all of their work on the four fields of the minor-league complex. But the most interesting stuff the Tigers did Friday occurred just outside the clubhouse door around 9 a.m. at their big-league field, Marchant Stadium, before the beginning of the formal workout. While infielders were practicing not catching pop-ups, Justin Verlander was in the bullpen behind the right-center fence having his latest throwing session. Verlander keeps throwing more pitches each time he gets on the mound. This time, he threw 60. As with everything else so far this spring with the big right-hander, all seemed to go smoothly. In his recovery from core-muscle surgery, Verlander has been throwing once every three days. In his next scheduled outing, on Monday, he could take the next step: Throwing live batting practice for the first time this spring. As outlined by manager Brad Ausmus, the best scenario is that Verlander’s entry into the exhibition season will be delayed by one start. If all continues to go well, he might not have to miss any time at the outset of the regular season. More than an hour after Friday’s full-team workout ended, and as 2 p.m. approached, Verlander was in the clubhouse studying video of himself with pitching coach Jeff Jones. For someone who hasn’t thrown to a hitter yet in camp, he’s typically hard at work. While Verlander was throwing in the bullpen Friday morning, Ausmus oversaw a drill on the Marchant Stadium infield. It involved four infielders: first baseman Miguel Cabrera, second baseman Ian Kinsler, shortstop Jose Iglesias and utility man Steve Lombardozzi. In the drill, an infielder would get under a pop-up as if he were going to catch it. Then he would let the ball drop at his feet untouched and throw it to second for a force-out. The apparent purpose of the play is to eliminate a speedy runner at first in favor of a slow one. For example, if Shane Victorino is on first for Boston with one out and David Ortiz pops up, the Tigers could let the ball drop and force Victorino. Then Ortiz, who is much slower than Victorino, would replace him as the runner at first. When asked about this drill, Ausmus said, “I don’t want to get into it.” He was then asked how many times in a full season the Tigers might employ this let-it-drop play.