Despite his top prospect status, I don't think the expectations for what Manny Machado would do in an Orioles' uniform this season were all that high. With Wilson Betemit on the DL though, the team need a third-baseman and decided to call up the 20 year-old from Double-A to fill in.
Machado started out well, hitting 3 home runs in his first 4 games, but since then has hit just .254/.267/.345 in 147 plate appearances (36 games). A 31 to 3 strike-out to walk ratio (overall) just isn't going to get it done in the Majors, but you don't need to be a plus hitter when you can handle the glove-work. As a shortstop, Machado unsurprisingly has solidified the hot corner for the O's - he's the only player with a positive UZR at the position this year (+3 runs), and is a big improvement over the likes of Betemit (-6 UZR) or Mark Reynolds (-5 UZR).
And even though the offensive production isn't there, given the alternatives it's still decent. Machado's .302 wOBA has translated into -2.2 runs relative to average in his 163 PA. Without Manny, the O's would have potentially had to go with a combination of Robert Andino, Omar Quintanilla, and Ryan Flaherty at third. The way they've hit this year, those three guys are at around -7, -3, and -6 runs in 163 PA, respectively. Combine that with losing some bench flexibility and potential platoon opportunities, and it seems fair to say that Machado has provided the team with upwards of 5 runs with the bat over what they would have otherwise been getting. With how close the AL East (and Wild Card) might be, that is certainly relevant.
Even if you ignore his hot start and assume he hit .254/.267/.345 all year, he'd still be a little above replacement level as a player; he's at +0.7 fWAR with -2.2 batting runs, so that translates into +0.2 fWAR with -7 batting runs with that triple slash. And that -7 batting runs is about what Andino would be expected to do over the same time period, so even the "slumping" Manny Machado doesn't really cost the Orioles anything.
More generally, this is probably good experience for Machado. He's holding his own in the big leagues despite not even getting a full year at Double-A. The lack of walks is a problem, but he hasn't been a complete hacker - he's swinging at pitches out of the strike-zone only slightly more often than league average (according to FanGraphs). Pitchers are pounding the zone against him though, and he's swinging and missing a fair bit. Still, there's enough positive signs to feel good about what Machado will be able to do in the near future - and, though scouting isn't my thing, he sure looks good out there.