Can Reds rookie Billy Hamilton maintain his hot streak?

Less than two weeks ago, in the wake of Travis d'Arnaud's demotion, I noted that the Mets' backstop wasn't the only heralded rookie struggling thus far. Among the handful of players I included in that class was Billy Hamilton, who for all of his blazing speed was getting on base at a .288 clip. Since then, the 23-year-old switch-hitting Reds centerfielder has caught fire, rapping out 16 hits in his last nine starts, with four consecutive multi-hit games earlier this week. Has he finally figured it out?

Hamilton's legend preceded his arrival in the majors, via triple-digit stolen base totals in 2011 (103 at Class A Dayton) and 2012 (155 at two levels). He reached Triple A in 2013 and swiped 75 bags, though he underscored the old adage "You can't steal first base" by posting an unimpressive .256/.308/.343 line. Even so, he was called up when rosters expanded and proved to be a weapon off the bench for the playoff-bound Reds, notching 13 steals despite just 22 plate appearances and three starts.

Cincinnati let centerfielder Shin-Soo Choo depart as a free agent this winter, leaving a massive gap atop its lineup. Choo's .432 on-base percentage from the leadoff spot was the majors' highest since Chuck Knoblauch put up a .448 mark in 1996, and to that he added considerable punch via 21 homers and a .285/.423/.462 overall line. Cringeworthy defense (-18 Defensive Runs Saved, −16.9 Ultimate Zone Rating) limited Choo's total value to 4.2 Wins Above Replacement, leaving a lower bar for his rookie replacement to clear.

Not surprisingly, Hamilton hasn't been able to match Choo's performance at the plate, hitting a modest .277/.313/.400 even with his hot streak, but adding 29 steals in 34 attempts. His .310 OBP from the leadoff spot is tied for 21st of the 25 players with at least 150 plate appearances in in that capacity, while his 94 OPS+ is tied for 17th. One point ahead in the latter department is Dee Gordon, who has hit .266/.320/.385 atop the Dodgers' lineup while swiping 31 bases in 36 attempts. The arc of Gordon's season is more or less the inverse of Hamilton's, in that he has cooled off considerably after a red-hot start.

Here's how Hamilton breaks down, month-by-month:

Split	PA	AVG/OBP/SLG	BABIP	OPS+	BB%	K%	P/PA	GB/FB
March/April	102	.245/.280/.330	.293	73	3.9	18.6	3.35	1.24
May	84	.260/.301/.351	.328	84	6.0	20.2	3.37	1.43
June	70	.344/.377/.563	.365	165	5.7	14.3	3.94	1.53

Within those small sample sizes is a narrative of progress. Hamilton has become a more productive hitter with each passing month. He's seeing more pitches per plate appearance, making contact more often, hitting the ball on the ground more often when he does and thus getting on base far more often. He's also shown more punch; after tallying just one homer and 10 extra-base hits through the first two months, he has three homers and eight extra-base hits in about two-thirds of a month.

However, the narrative isn't as definitive as that. Hamilton has actually swung at more pitches outside the strike zone with each passing month (25.8 percent in April, 29.9 percent in May, 30.3 percent in June). Additionally, he has struggled against lefthanded pitching, batting .226/.258/.339 in 68 PA against southpaws overall, compared to .295/.333/.422 in 188 PA against righties; his BABIPs in that split are .260 and .348, respectively. While he had one walk and two extra-base hits (both doubles) in 47 PA against lefties prior to June, he's got one walk and three extra-base hits (one homer) in 21 PA against them this month, and he has yet to clear a .286 OBP against lefties in any month. Take away that homer — the only one Brewers lefty specialist Will Smith has allowed against the 141 batters he's faced this year — and Hamilton's 2014 OPS by month against lefties would read .351, .667 and .566. The homer happened, but it's hardly clear that it was anything but a fluke.

As Hamilton has heated up, so has the Reds' offense. They went 25-29 while averaging 3.44 runs per game through the end of May but are 10-7 while scoring 4.59 per game in June. One can't hang all of those early struggles on the leadoff hitter, as injuries limited Joey Votto and Jay Bruce to 12 games apiece in May, and just three starts in the same lineup. Neither has hit nearly as well as last year, when they were two of the only three Cincinnati regulars with an OPS+ above 100 (Votto 155, Bruce 119, with Choo's 144 the other). This year, Votto is at 138, Bruce at 84 (on a dismal .211/.311/.353 line), with Todd Frazier (137), Ryan Ludwick (110) and Devin Mesoraco (157) the other above-average contributors, though the latter two share jobs with subpar hitters, lessening their impact. Overall, the Reds are still just 12th in the league in both scoring (3.75 runs per game) and OPS+ (88), and they're 13th in on-base percentage (.304). That lack of offense is why they're still below .500 (35-36) despite allowing just 3.77 runs per game, the league's fifth-best mark.

It's on the run prevention side where Hamilton has helped Cincinnati the most. He's been a huge improvement over Choo according to both DRS (+8) and UZR (+9.7), which has helped to offset his slow start with the bat. Thus, he has been worth 1.8 WAR through the Reds' first 73 games, a prorated pace that would equal 4.0 WAR over a full season — making the tradeoff between him and Choo a break-even one, at a fraction of the price.

Just as it was too early to dismiss Hamilton as a complete bust based on his play through the end of May, it's premature to conclude that his hot streak is anything more than just a good couple of weeks. His speed makes him one of the game's most exciting players, but given his ongoing platoon issues, manager Bryan Price would do well to move Hamilton down to the bottom third of the lineup against lefties, since the roster lacks a capable enough partner to justify outright benching him; righty Chris Heisey's career .216/.272/.396 against southpaws is no more playable given the step down in defense.

For the Reds to climb back into contention, general manager Walt Jocketty would do well to find a better complement; if cloning Oakland's Craig Gentry is out of the question, then even a return of Drew Stubbs (who was dealt away as part of the December 2012 trade that brought Choo to Cincinnati) would help. Hamilton may still pan out as an above-average player, but a bit less of him in the lineup could mean a bit more for his team.