BALTIMORE -- It is the sort of line that a team encounters a few times a decade, if that.

Andrew Miller walked six batters, a recipe for disaster. Yet when in the strike zone, his stuff was so good that he still managed to toss 5 2/3 shutout innings in which he allowed just two hits and struck out three. It was an outing in which he was mostly dominating, with a couple of hiccups in which he and the Red Sox managed to escape disaster en route to a 4-0 victory over the Orioles.

To put Miller’s unusual line score in context: The last time a Sox starter tossed at least five shutout innings while walking six or more was in 2005, when Matt Clement accomplished the feat. Prior to that, it had occurred in three starts by a Sox pitcher in the ‘90s, none in the ‘80s and four times in the ‘70s.

The rare accomplishment by the left-hander offered two simple conclusions:

First, Miller remains a work in progress. He has walked (in order) four, five and six batters in his last three starts, a total of 15 free passes in 13 1/3 innings.

Secondly, when he throws strikes, he has overpowering stuff.

There is no getting around the fact that Miller remains a project with whom the Sox must walk something of a tightrope. In the first couple of innings, despite the fact that he did not allow a hit, his day nearly fell apart.

He threw 10 of his first 11 pitches for strikes, then missed the zone with 17 of his next 27 offerings. In the process, he walked the bases loaded with one out in the top of the second. He did not mask his frustration, snapping at the ball on return throws to the mound and seemingly reaching wit’s end. He also appeared to be losing trust in his fastball, babying it towards home at 89-91 mph.

But then, in a pivotal sequence, he righted his outing. Miller threw a first-pitch fastball for a foul ball to Craig Tatum, then fell behind when his next two pitches (both changeups) were in the dirt. But at that point, in a game-defining stretch, he threw a 93 mph fastball (foul), 92 mph fastball (foul), 79 mph curveball (foul) and then elicited an inning-ending 4-6-3 double play on a changeup.

“I definitely lost the zone there for a little bit. You don’t like it to take that long to find your way back into it. It is what it is, but fortunately, I was able to escape,” said Miller. “[The double play] was huge. Who knows how the game would’ve gone if we don’t get that, or that ball goes in the hole, or I fall behind?

“I think that was kind of the momentum shift,” Miller added. “They probably had it there when they loaded the bases, and it probably deflated them a bit when they didn’t get anything out of it. So, it was nice, and fortunately, I was able to kind of get in a groove after that.

It is a fine line for the left-hander. He acknowledged that he is still at a point where he must consider his mechanics. He goes through stretches in which he loses his release point and then cannot find the strike zone. But when he can lock it in, then his ability to throw strikes with three pitches lends itself to an ability to mow through an opposing lineup.

“There’s a lot of moving parts there. He’s a big, lanky kid. If he’s missing his release point, the ball kind of is scattering a little bit,” said manager Terry Francona. “When he’s good, he’s throwing his changeup for strikes, his breaking ball for strikes and his fastball for strikes. And he locates.”

For much of Wednesday afternoon, Miller did just that. Buoyed by his escape from the second inning, he sailed for the next three innings.

Starting with the double play, he retired 12 of 14 batters, with both baserunners coming on singles. His fastball ticked up, regularly hissing through the zone at 91-95 mph, and he showed a well-rounded three-pitch mix with which the Orioles could do little.

It was a reminder that if Miller throws strikes – and pitches with confidence that he can throw strikes – then outs, lots of outs, can follow quickly. In many respects, he is not as reliant on command as other pitchers might be. His stuff and delivery (when working) allow him to get bad contact even on pitches over the plate.

“He pitches to the middle of the zone a lot. His stuff and deception is so good that he’s able to get away with a lot of pitches and just get weak contact early in the count. He knows that,” said teammate Daniel Bard. “It’s not like when he goes out there and walks three in a row that he’s trying to pitch away from contact. Stuff like that happens. But he’s out there competing and that’s what we needed today.”

Miller, whose ERA dropped from 5.68 to 4.65, has indeed been able to compete and give the Sox a chance to win in all but one of his outings. He now owns a 4-1 record, while the team is 5-1 when he takes the hill.

In many respects, that is the bottom line. He is working to achieve the consistency of his mechanics that has eluded him for much of his career, and based on his performance thus far this year in both Triple-A and the majors, he is closer to achieving it than he has been at many stages of his career.

Yet he remains a work in progress, something that he acknowledges. But by virtue of the fact that he has averted disaster – he has permitted three or fewer runs in four of his five starts – he has given the Sox a chance to win, and earned the right to continue to work through and manage his struggles.

“I’m looking forward to the day maybe where I can go out there and not think about it at all and throw a strike every time. I don’t know if you ever get to that point, but I’m working on it. It’s a process,” said Miller. “Ultimately I’ve got to do a better job, and that’s kind of what the regrouping I did in Triple-A to get me called up here. So, I know I’m capable. It’s just a matter of working out the kinks with [pitching coach] Curt [Young] and go get them next time.

“Obviously, I’d like to pitch deeper,” he added. “Shoot, I’d like to pitch nine innings every time out. But I think ultimately what really counts is if you get a win at the end of the day, and fortunately, we’re doing that when I pitch and whenever anyone else pitches, too.”