When you think of lineups that will bludgeon pitchers in 2021, do the Astros still come to mind?

George Springer is now a Blue Jay, and it might take weeks to adjust your eyes for that. Jose Altuve is coming off a career-worst season. The Astros, as a whole -- after challenging MLB records for team offense several years running -- were exactly league average (100 wRC+) with the bats in 2020. After a dreadful spring dealing with the fallout from its sign-stealing scandal, Houston never seemed on-track -- at least, not until October.

But if you’ve perused FanGraphs’ Depth Charts projections and sorted the offensive WAR column lately, it turns out some things stay the same: There’s the Astros, projected as having MLB’s top attack in 2021 ahead of the Yankees, Dodgers and Springer’s Blue Jays. And here’s one overlooked reason why Houston’s No. 1 -- Air Yordan might be back.

Yordan Alvarez, remember him? A quick refresher: Alvarez came up to the big leagues two Junes ago and made The Show look easy, packing 27 homers and 78 RBIs into just 87 games as the second coming of Willie McCovey’s rookie campaign. His adjusted 173 OPS+ was the most by any rookie with 350 plate appearances since Shoeless Joe Jackson (193) in 1911. It was one of the best freshman campaigns, and Alvarez was the deserving and unanimous American League Rookie of the Year Award winner.

To the question of whether Alvarez could ever repeat all that, the answer was … well, we’re still waiting on that. Alvarez missed the first three weeks of last season after testing positive for COVID-19, came back for all of two games and then was shut down for the rest of the year with a torn patellar tendon. He wound up needing arthroscopic surgery on both of his knees.

That makes Alvarez both the biggest question mark and the biggest potential internal upgrade for any team entering this season. While he’s shared some workout videos on social media this winter, we really won’t know anything until we see Alvarez at Spring Training.

But if (and it’s a large if) Alvarez can return healthy, that could have a big impact for the Astros. Here’s what Houston could bring back to its lineup without having to spend a dime on the free-agent market.

Big-time power, big-time projections

Let’s start with this: There was nothing fluky about Alvarez’s rookie year. He absolutely hammered pitches, as you might recall. And while there was some swing and miss in his game, he showed impressive discipline overall.

We’ll spell that out a little, but first, just admire all the red here:

Broken down, those metrics included:

• A roughly 49% hard-hit rate, tied for 15th best across MLB (min. 200 batted balls). Even better: a roughly 17% barrel rate -- just outside MLB’s top five. Not only did Alvarez pummel balls; he launched them, too.

• A .292 expected batting average (xBA) and .414 expected weighted on-base (xwOBA), a top-30 and top-10 mark, respectively, that were even a little more impressive, considering those metrics baked in Alvarez’s above-average strikeout total.

• A roughly 14% walk rate (top 20), showing how Alvarez could affect the game even when he wasn’t going yard. Plus, Alvarez was a top-25 hitter by MLB senior data architect Tom Tango’s swing/take decision metric, and he finished with above-average run value marks against all but one pitch type.

That’s a lot we just threw at you, basically to say that Alvarez both slugged and showed the plate-discipline characteristics of a veteran star. He was all of 21 years old when he debuted, and he’d logged only 250 Minor League games before his callup.

These are all reasons why leading projection systems, like Dan Szymborki’s ZiPS, are bullish on Alvarez this year. In fact, he’s ranked sixth in ZiPS’ OPS forecast for 2021, and seventh by wOBA, sandwiched between teammate Alex Bregman and Bryce Harper, at a robust .378. It’s worth noting that Szymborski harbors the same reservations we all have about a designated hitter coming off double knee surgery (and ZiPS only projects him to play in 104 games).

“I love watching Yordan Alvarez when he turns on a pitch,” Szymborski wrote in his Astros 2021 preview, “but I’m slightly more worried about him than ZiPS, which clearly isn’t too troubled by his largely missed season. But 2019 was a huge step forward for Alvarez, and I think there’s some risk in losing what ought to have been a consolidation year for him. I think he’ll still be awesome, but that concern is floating there in the periphery of my brain.”

Szymborski’s words sum this up well. Alvarez might be an elite hitter on paper, but we don’t know what he’ll actually give Houston until he’s out there getting four to five at-bats a night.

But if the 2019 Yordan Alvarez returns, well, that’s as big an addition to the Astros' 2021 lineup as just about any free-agent bat out there this winter. Remember, Alvarez homered in his first at-bat back last year, and it was crushed the other way. If he’s feeling that good this spring, look out.

Win from within?

A healthy Alvarez isn’t the only reason why the Astros’ lineup could dominate again. Bringing back Michael Brantley’s extremely professional at-bats could be huge. Altuve’s track record suggests he’s far likelier to rake than struggle again (and he might have already returned to form in the postseason). ZiPS is also high on Kyle Tucker (124 OPS+, 27 HR, 103 RBI) as he takes Springer’s place in the outfield. The Astros could (and probably should) still add a center fielder, but if that player and Brantley wind up being their two biggest position-player signings, a quiet offseason could actually pay off nicely.

A team that finished one game shy of the World Series with a downgraded offense projects to be more potent, mostly via internal improvements -- even sans Springer. If that happens, the return of Air Yordan will probably be a big reason why.