The San Francisco Giants already had their work cut out for them this season.

After an aging team lost 98 games last year, the Giants eschewed a full rebuild and went to Spring Training with a few new veteran faces, and a big ol’ goal: making the postseason in 2018.

In the National League West — a division that has the dominant Dodgers and put three teams in the playoffs last year — that’s a daunting task. It was, no doubt, going to take a charmed season and an inspired, full-force effort across the Giants’ roster.

So when two of the Giants’ three-best starting pitchers from an already suspect rotation go down with injuries in the final two days of spring training in Arizona, I feel it’s fair to get down on San Francisco’s prospects for the 2018 campaign.

And if the Giants don’t reach their goal — making the playoffs — this year, that opens up a Pandora’s box of possibilities, with few good options flying out.

When Giants’ No. 3 starter Jeff Samardzija went down with a pectoral injury on Thursday, my initial, knee-jerk dourness towards the Giants’ chances to make the playoffs this season was disproportionate. Yes, the Shark is a good pitcher, and yes, the rotation was already relying on two unproven starters before the injury, but it’s not as if the Giants lost their ace or anything….

Then, on Friday, they did, when Madison Bumgarner was hit with a comebacker in his left, pitching hand, breaking his fifth metacarpal (also known as his pinky).

The baseball season is long and unpredictable, but forgive me for thinking that with these injuries, and particularly Bumgarner’s, the Giants’ season — with its singular possible success — is over before it even began.

Let me explain:

Samardzija is expected back in three to four weeks — so that’s late April or early May — and Bumgarner has no timetable for his return, though he is having surgery Saturday to place pins in this hand, which will remain in place for four to six weeks. After the pins are removed, he won’t be able to simply pick up a ball and throw it 93 miles per hour, but the recovery time is unknown — Bumgarner is hoping it’s before the All-Star Game.

But will the Giants have anything to play for by the time Bumgarner returns, lets say in eight to 10 weeks?

Getting out to a fast start has been a talking point for the Giants all of spring training, and for good reason: last year San Francisco was seven games back in the division by the end of April and 10 games back by May 9. In effort to re-establish themselves as a top team again in the early goings of the 2018 season, the not-so-well-kept secret was that the Giants were going to use the team’s multiple off days to start Bumgarner in three of the team’s first nine games.

A fast start might not be a clear-cut, no-negotiation imperative for the Giants — all the games count the same, after all — but the idea wasn’t being discussed by players and coaches as a hobby.

A strong start to the season was particularly important for the Giants because of the difficulty of their schedule in the opening weeks: they have three separate series against the Dodgers before the end of April, in addition to two series against the Diamondbacks, and one each against both the Nationals and Angels.

That might be toughest early-season schedule in all of baseball, and if the Giants played well against those opponents, it would no doubt create a momentum — or at least a belief — that could carry them far.

How likely do you think that momentum is created now?

At the moment, the Giants head into the season with a four-man pitching rotation of Johnny Cueto, Ty Blach, Chris Stratton, and Derek Holland.

Cueto might be a solid pitcher, but unless he’s going to tap back into his Cincinnati form, he’s no longer a true No. 1 starter. Blach and Stratton might both have plenty of upside, but both are also unproven. The Giants’ rotation was already a question mark when they were the fourth and fifth starters — now they’re No. 2 and No. 3. And Holland might have earned himself a job with a nice spring, but he had a 6.20 ERA last season and a 5.50 ERA over the last three years.

We don’t know who the Giants’ fifth starter even is — though they’re unlikely to need one until April 10, based on the way the schedule lookst. That said, San Francisco might need a veteran free agent who was recently cut from a camp to fill out the rotation.

The Giants broke camp feeling good about their bullpen and lineup — as they should — but this bullpen isn’t strong enough to handle the tax this team’s starting pitching is about to impose (no bullpen is), and the lineup, while solid, is still heavily comprised of players who helped the Giants finish last in baseball in home runs and OPS last year (this is a reminder improved doesn’t mean great).

This is a team that was looking at a .500 record fully healthy. It was a squad that could have realistically found some luck and squeezed out the few extra victories necessary to finish the season with 87 wins, the magic number to make the playoffs as a Wild Card in the National League over the last few years. Again, a big ask, but possible.

But without Bumgarner for an extended period of time and Samardzija eating innings for roughly a month, wins are coming off the board, and that makes it that much harder to envision the already unlikely scenario where the Giants are playing in October.

The 2018 season is a make-or-break year for the Giants as we know them.

Can they weather the storm for the next few weeks and make something out of this campaign?

Or was it broken along with Bumgarner’s pinky on Friday?

San Francisco’s ownership group and front office considered a full, burn-it-down rebuild during and after last season’s 98-loss debacle. Both parties opted against it because of contractual obligations, business interests, and the belief that this World Series-winning core still could produce.

If the hellacious early-season schedule and a now far-less-than-trustworthy rotation effectively ends the Giants’ season before Memorial Day — again — how will that conversation go in 2018?