On Friday, Dallas Keuchel will make his first regular-season start since last September, some 265 days ago. His appearance will serve as his debut with the Atlanta Braves, having signed with the club in early June following a prolonged free agency. Keuchel's will be going up against the surging Washington Nationals in the opener of an important three-game set. First pitch is at 7:05 p.m. ET and fans in the Atlanta market can stream his start via fuboTV (Try for free).

Because Keuchel is getting a late start, and because it's been some time since most people have seen him throw -- he did make two minor-league appearances ahead of his activation -- we figured it might be helpful to put together a guide on how to evaluate his readiness. With that in mind, let's take a look at four aspects to keep in mind heading into his first start.

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Dallas Keuchel will make his debut on Friday, just don't expect him to light up radar guns. USATSI

1. Velocity

We may as well start with the most easily measured part of pitching. Truthfully, throwing hard isn't Keuchel's thing. Last season his sinker clocked in on average at 89.2 mph, the ninth-slowest in baseball among pitchers with 2,000-plus pitches, per Statcast.

Keuchel might rank even lower this year, too. A team source told CBS Sports that his fastball sat in the 87-to-89 mph band during his minor-league starts. There are numerous potential explanations at play -- ranging from him not throwing at max effort to him having not shed all the rust from a lengthy layoff -- that could mean his slightly reduced velocity is just a blip on the map.

But even if Keuchel's velocity is down a tick heading forward, other elements have and will continue to dictate his fortune more so than his raw radar-gun readings.

2. Command

Command is one of those nebulous concepts that many people misinterpret or misuse. It isn't as simple as whether a pitcher is throwing strikes; it's a matter of throwing quality strikes, or sometimes intentionally throwing a ball, as a chase or set-up offering.

In a sense, command is about pitch mastery.

In Keuchel's case, that means leveraging his arsenal depth the way he desires, by spamming the lower chunk of the zone with his sinker. It also means burying his cutter inside against right-handed batters, keeping his changeup on the opposite side of the plate, and making sure his slider looks tempting enough to coerce swings.

Remember, Keuchel adheres to a pitch-to-contact philosophy, which entails managing the quality of contact made against him. That necessitates a precision -- and constructs a thinner margin-of-error -- that pitchers more reliant upon power don't have to concern themselves with.

If Keuchel has a bad outing, it's probably because his command isn't quite there yet.

3. Sharpness

Alternatively, a rough Keuchel outing could mean his pitches aren't as sharp as usual. Do note that by "sharp" we mean the quality of the pitches themselves.

Keuchel doesn't blow batters away, but last season four of his five offerings featured above-average movement on at least one plane -- be it horizontal or vertical -- as compared to pitches with similar velocity, per Statcast. The amount of movement and the quality of it -- a pitch that appears to "break late" is more effective than one that appears to "break early" -- are vital for any pitcher, and particularly for one who needs the opposition to mishit his pitches.

Keuchel's sinker is his primary pitch, and it's fair to say that's the most important piece of his arsenal. He has to locate it for strikes and he has to have enough movement on it for batters to top it into the ground over and over. But his slider and changeup are also pivotal, in that they represent his best bat-missing offerings.

Keep an eye on how Keuchel's pitches are moving throughout the night. Or, at minimum, just watch the batters' swings. They'll tell you all you need to know about how good his stuff looks.

4. Stamina

Think of this as the final exam -- the one that requires applying everything that came before it. Judging a pitcher's stamina is about more than looking at his pitch count, it's about noting how all those previous elements hold up during the course of a start.

Is Keuchel holding his velocity once he gets into the fourth or fifth inning, or is he topping out around 87 mph? Has his command wavered, leading to more target-missing -- particularly "bad" missing, over the plate or in other nitro zones? Do his secondary offerings still have their effectiveness? And so on..

Keuchel topped the century mark in pitches thrown last time out, and it stands to reason the Braves will let him work as deep into games as he can. But if manager Brian Snitker yanks Keuchel earlier than expected, it's likely because he finds the answers to the above questions unsatisfactory.