The vast majority of preseason prognosticators pegged the Pirates as a back-end team in the National League Central, their rebuilding project not quite ready to make any real noise in the division.

When Oneil Cruz went down with a fractured left fibula less than two weeks into the season, the outlook became even more grim.

Yet here we stand in the first week of May and Pittsburgh sits atop the NL Central -- despite being swept this week by the Rays and their 26-6 record -- a development that 15 of 20 voters chose in the “biggest surprise team” category in this week’s MLB.com executive poll.

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“Their success isn’t a blip,” an NL executive said of the Pirates, who are coming off back-to-back 100-loss seasons. “They’re showing they can sustain it and fight with the best.”

Sustaining for a few months is one thing. Can the Pirates actually conquer the 162-game grind to reach the postseason for the first time since 2015?

Many of the executives polled don’t think so, with 15 predicting a third- or fourth-place finish. Only one executive picked Pittsburgh to win the NL Central, while two predicted a second-place finish. None of the respondents, however, believe the Pirates will wilt badly enough to find themselves in last place by season’s end.

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“I don’t think they quite have the roster talent to win the division,” an NL executive said. “But already being [eight] games over .500 should keep them out of the basement even if they cool off.”

As of Thursday, the Pirates ranked fourth in the NL in runs scored, thanks in large part to a running game that leads the Majors with 44 stolen bases. The club’s collective .769 OPS ranked fourth in the NL, while its 68 doubles and nine triples were each tops in the NL.

“They could finish first if they can keep this momentum,” an NL executive said. “They could use a little more production from guys, but defensively, Ke’Bryan Hayes has been solid and so have some of the young arms in the rotation.”

Led by a rejuvenated Vince Velasquez (3.06 ERA) and homegrown arm Mitch Keller (3.32 ERA), the rotation ranked fifth in the NL with a 3.84 ERA, while the bullpen -- anchored by All-Star closer David Bednar -- ranked second with a 3.21 ERA.

One NL executive praised the Pirates’ “youth and overall depth of their roster,” while another called Pittsburgh a “great story” to this point in the season.

Still, many executives are skeptical that the Pirates will be able to keep up this level of play for five more months.

“The Pirates will finish second or third behind Milwaukee and possibly the Cubs,” an NL executive said. “They’re solid, but I’m not sure how they’ll handle another big setback or two or a losing streak. I’m also not sure the depth will be super powerful or exciting; it will be soon in another two years or so.”

The biggest issue the Pirates could face in the coming months is rotation depth, a theme mentioned repeatedly by rival execs. Through Thursday, the Pirates had used the same five starters through their first 32 games, but an injury or two could leave them in a precarious position after JT Brubaker and Mike Burrows were lost for the season to season-ending surgeries.

That situation might have arrived Thursday, when Velasquez left his start against the Rays after only three innings with right elbow discomfort. The club’s top pitching prospect, Quinn Priester, has a 7.78 ERA in five starts at Triple-A, though its No. 8 prospect, Luis Ortiz, has a 2.45 ERA in six starts for Indianapolis, making him the likely candidate to get the call if needed.

“Their lack of Major League-ready pitching depth will rear its head over the course of the season,” an AL exec said. Added another AL decision-maker: “The Pirates will fade based on roster depth and playing a more challenging schedule, but they’ll still manage to finish third.”

Among those who picked the Pirates to fall back in the standings, the belief that the Brewers, Cubs and Cardinals are simply deeper and more talented was the primary reason given.

“As fun as Pittsburgh’s start has been -- and though they certainly do have talent -- the Brewers, Cardinals and Cubs have the talent and depth to chase them down,” an AL executive said.

“The season is long,” another AL exec said. “There’s plenty of time to regress to their preseason expectations.”

Or, perhaps, the Pirates are putting themselves in position to shock the baseball world and bring their eight-year playoff drought to an end.

“… I think it’s a pleasant surprise given their recent years,” an NL executive said. “They have some young talent and solid players. It should be interesting to see if they can maintain the momentum as the season continues.”