ALCS preview: Player to watch, key matchup, and more for Royals-O's

Get ready for the ALCS between the Royals and Orioles with our in-depth series preview, featuring the stat to know, player to watch, key matchup and more.

The Royals won their regular-season series against the Orioles and outscored them 26-18, but that won't matter at all when Kansas City's James Shields takes the mound against Baltimore's Chris Tillman in Oriole Park at Camden Yards on Friday night. The last time these clubs faced off was nearly five months ago, on May 18, when both were hovering around .500. They are both very different now, as their twin divisional series sweeps only begin to suggest.

• Complete postseason schedule, start times and TV listings

Player To Watch: Eric Hosmer, Royals 1B

When July ended, the Royals were 55-52 and 3 1/2 games out of a Wild Card spot. When September began, they were 74-62 and not only in wild card position, but also tied with the Tigers atop the AL Central. August was when the Royals transformed from potential-laden lurkers to likely playoff participants, but their season-best 19-11 record that month came almost entirely without the services of Hosmer, their 24-year-old first baseman. A stress fracture in his right hand put him on the DL on Aug. 1, and he didn't return until Aug. 31, when he struck out in a single pinch-hit at-bat.

Looking ahead to Orioles-Royals ALCS: Defense, bullpens will be key

The truth was that Hosmer hadn't given the Royals much to miss. At the time of his injury, he was hitting .267 with six home runs — far from the production the club could have expected from a corner player whom Baseball America once ranked as the game's eighth-best prospect. In September, Hosmer showed signs of improvement — he batted .290 with three homers and an OPS of .841 — but even that could not have prepared the Royals for a postseason in which he has emerged as their most dangerous offensive player.

Yes, it's only been four games, but what a four games it's been. Hosmer has seven hits in his 14 playoff at-bats so far, and four of them have gone for extra bases. Even more important has been the timing of them. In the 12th inning of Kansas City's Wild-Card Game against the Athletics, with his club trailing 8-7 and two outs from its season's end, Hosmer lashed a triple off of Dan Otero and then scored the tying run. In the 11th inning of an ALCS Game 2 against the Angels that was tied at 1-1, he smashed a near-400-foot, two-run shot off Kevin Jepsen to give the Royals their ultimate lead. He hit another crucial two-run bomb two nights later, this one in the third inning against Hector Santiago; those RBI proved to be the game- and series-winners.

You might have seen that Hosmer led the celebrating after that one, and he deserved to do so. The Royals' success is predicated on solid pitching, terrific defense and timely hitting, and Hosmer has become their timeliest hitter of all.

Key Matchup: Caleb Joseph vs. Terrance Gore

While the Royals' and Orioles' pitching staffs are similar — both feature effective starters and dominant relievers (more on them below) — the offenses represent a significant contrast in styles. The Orioles hit the most home runs in the majors (211); the Royals hit the fewest (95). The Royals stole the most bases in the majors (153); the Orioles swiped the fewest (44).

A young Royals team realizes its talent in ALDS sweep of Angels

The Royals have become kleptomaniacs in the playoffs — they have 12 steals in four games, including a playoff record-tying seven in their game against the A's — and the 23-year-old Gore proved himself to be their swiftest thief. The 5-foot-7 outfielder has a single major league at-bat to his credit, but he is so quick that when you watch him run on TV, you're tempted to call your cable provider to report that your feed's somehow skipping ahead.

Gore will likely again be limited to crucial pinch-running situations, but teammates like Nori Aoki, Lorenzo Cain, Jarrod Dyson and Alex Gordon are also liable to run at any time, and that means that Caleb Joseph will likely receive most of the work behind the plate for Baltimore. Joseph started only one game in the ALDS against the slow-footed Tigers, to his platoon mate Nick Hundley's two, but Joseph could be the significant impediment to a running game like Kansas City's. He gunned down a Molina-like 40 percent of basestealers this season, to Hundley's 14 percent. His arm could help decide several of this series' games.

Stat To Know: 137-11

That was the combined regular-season record, translating into a winning percentage of .926, for these clubs when they carried a lead into the seventh inning. The Royals' late-inning Cerberus of Kelvin Herrera, Wade Davis and Greg Holland has gotten more press, but the Orioles' bullpen — especially setup men Andrew Miller (who had a 1.35 ERA after coming over from Boston) and Darren O'Day (1.70) and closer Zach Britton (1.65) — has been nearly as good.

Buck Starts Here: Showalter leads Orioles to long-awaited ALCS

In fact, Baltimore's bullpen might represent an advantage in the ALCS for a couple of reasons. One is that while Royals manager Ned Yost likes to stick stubbornly to a formula that has Herrera pitch the seventh, Davis the eighth and Holland the ninth, Orioles skipper Buck Showalter has demonstrated far more flexibility, using his best arms in high leverage situations whenever they occur. Another is that the Royals' relievers have recently shown signs of vincibility.

Herrera had to leave Game 1 of the ALDS after only one batter due to forearm tightness, and while he returned to pitch a perfect inning in Game 3, such injuries can reappear at any time. Davis — he of the 1.00 ERA in the regular season — has worked at least an inning in all four of the Royals' postseason games so far, but he uncharacteristically allowed the leadoff batter to reach base in each of the last three of them, and ended up allowing just one run due largely to the stellar defense behind him.

Roster Snapshot: Depth issues

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It is something of a miracle that the Orioles have made it this far despite sustaining season-ending injuries to two of their best players, Manny Machado and Matt Wieters. This might be the series in which the absence of those stars is felt, primarily because of the depth issues it has created. Delmon Young is the first bat off the bench — he was 10-for-20 as a pinch hitter this year, and he stroked the three-run pinch-hit double in the bottom of the eighth that beat the Tigers in Game 2 of the ALDS — but he is a miserable fielder. The Orioles' other likely non-catching reserves — Kelly Johnson, David Lough and Jimmy Paredes — are mediocre hitters at best, and only Lough holds any defensive value.

Kansas City's bench, meanwhile, includes not only the extraordinarily speedy and defensively superior Dyson and Gore, but also the slick-fielding rookie infielder Christian Colon, who batted .333 in 45 regular season at bats, and the experienced masher Josh Willingham. Unusually long games will favor the Royals, and we know by now that the Royals love playing unusually long games.

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The Orioles' sweep of the Tigers meant that Davis won't be eligible to return from his 25-game amphetamines suspension until Game 6. Showalter, therefore, won't include him on the ALCS roster, as that would have compelled him to make it through five games with only 24 eligible players. But it would be shortsighted to conclude with certainty that Davis won't appear in this series.

Five games is plenty of time for an Oriole to suffer an injury (or an "injury," perhaps), and Davis would make for a valuable, and lineup-lengthening, mid-series replacement. He scuffled after his near-MVP season last year — his batting average fell from .286 to .196, his homers from 53 to 26 — but he would still represent a considerable threat as an insta-slugger that could be inserted into the lineup alongside fellow 20-plus home run hitters Nelson Cruz, Adam Jones and Steve Pearce.

Prediction: Royals in six.