Mike Miller is a really good three-point shooter. If he stays healthy, he should be able to space the floor for the Cavs' offense. The end.
That's how many have assessed what Miller's presence will mean for the Cavaliers this season. It's well known that Miller is a solid three-point shooter; he's a career 40.9 percent shooter from the outside, and shot 45.9 percent from three for the Memphis Grizzlies last year. (William Bohl breaks down his and other Cavs' three-point shooting here). It's also well-known that Miller's had injury issues over the last few years. Even though he played all 82 games for the Grizzlies in 2013-2014, while as a member of the Miami Heat, Miller frequently had to get regular season rest, due to injuries to his thumb, knee, groin, and back. However, it often feels like this is where the analysis ends with Miller.
Instead of continuing to tell what is already known about Miller, I'd rather focus on the other parts of Miller's game, especially as Miller has somewhat struggled to shoot the ball consistently through the first five preseason games. Miller is going to have to do more on the court than simply spot up and take threes, and that's what could keep Miller on the floor, even if his shot isn't falling.
Perhaps Miller's most underrated strength is his ability to finish at the rim, especially off cuts and drives. While a small sample size from last year, Miller hit 65.8 percent on lay-ups per NBAwowy, and he has consistently hit over 60 percent in the paint throughout his career. He's adept at finding space in the defense with off-ball cuts, and while he's not as good as a Luol Deng or Andre Iguodala, it's an effective part of his game in limited looks. He also scored 1.5 points per possession on 20 drives last season, an impressive efficiency. Simply put, Miller can finish at the rim, a fact that should not be lost on Cavs fans after the dearth of effective finishing over the last few seasons.
Defensively, Miller has been solid in the past. He has had decent quickness and the size to be able to serve as a competent wing defender, and did so on those Miami championship teams quite nicely. However, he's bound to continue to decline, after he struggled to make an impact on that end for the Grizzlies last year. The Grizzlies were almost seven full points better defensively with Miller off the floor compared to on, and this wasn't just a case of Miller playing with second unit guys on a good defensive team. Lineups with Miller and Marc Gasol had a defensive rating of 115.4, and the 65 minutes the Grizzlies played with Miller replacing Tayshaun Prince with their starters resulted in a 126 defensive rating, somehow. Beyond that, Miller looked a step slower, and noticeably seemed to conserve his energy for offense last season.
On the Cavs, that likely means that they are going to have to be somewhat judicious about the lineups that Miller spends a majority of his time with. Miller and Kyrie Irving probably can't be a backcourt pairing without LeBron James, for instance, because the Cavs would be prone to allowing too much dribble penetration with those two guarding backcourt threats, particularly against the two-PG lineups that teams like Toronto and Brooklyn are going to try to employ.
Miller instead, ideally, needs to be with a rim protector and versatile pieces that can allow the Cavs to efficiently hide him against a variety of lineups. The most effective defensive lineup that Miller played with last year (min. 30 minutes) did just that: Nick Calathes, Tony Allen, Jon Leuer, and Kosta Koufos played 39 minutes with Miller and posted a defensive rating of 84.2, and having Allen and Leuer with Koufos behind them let Miller hide on the other team's weakest scorer among the two, three, or four. For the Cavs, a lineup to mimic this could be something like Matthew Dellavedova, Dion Waiters, Miller, LeBron, and Tristan Thompson.
The final piece of Miller's game that could be very important to watch this season is his rebounding. Miller has been a strong defensive rebounder throughout his career, but his numbers fell off the map last year, as he ended a streak of five years with a defensive rebounding rate over 16, sliding to 12.3 percent. Miller's effectiveness on the glass made him less of a liability while he was hampered by injury in Miami, because the Heat could still get use out of him even if he was not a fit at all for their aggressive defensive scheme. Whether his drop-off in Memphis was a product of scheme or decline isn't known, though, and since the Cavs appear to be a team that wants to bang the defensive glass to end possessions and get out on the break, it would be really nice if Miller could go back to his solid rebounding numbers, especially because that would give him a defensive role even as the Cavs try to hide him off the ball. Miller's averaged 1.8 rebounds per game this preseason for a DRB% of 14.2, per RealGM, so that's an improvement; however, we'll have to see if that holds up in the regular season.
Miller's three-point shooting is obviously the big reason he sees floor time this season. We knew that already. However, other aspects of his game are going to have significant impacts on the Cavs' play when he sees the floor. How well Miller can finish at the rim, whether he can regain form on the defensive glass, and just how big of a liability he will be defensively are the big questions that will point to how effective Miller is on this team, especially if his preseason shooting slump continues to hold.