SOX ARE THIRD RATE AT THIS KEY POSITION

When he was a kid in the lowest levels of professional baseball, Pablo Sandoval spent most of his time at catcher and first base — one position at which defense was the name of the game, and one position at which hitting was key.

Since breaking into the majors, Sandoval’s settled into a job that demands both a glove and a bat.

“I think third base is different,” he said. “It’s a tough position to play. You have to have good defense, and not only perform in the field, but (also) hitting. It’s both sides. If you’re doing both, you’re going to be great.”

Though you wouldn’t know it watching the Red Sox cycle through one underwhelming option after another, baseball is experiencing a surge of third base greatness.

According to the FanGraphs measurement of wins above replacement, five of this season’s top 21 position players, and six of the top 25, have been third basemen. That’s with three big-name third baseman — Josh Donaldson,

Adrian Beltre and David Wright (Mets) — on the disabled list.

As of Thursday, 21 teams were getting an OPS of .687 or better from their third basemen. Six American League teams were getting less offense from their designated hitters.

Presuming an even distribution across eight positions, you’d assume the top 100 position players by WAR would include roughly 12 players at each position. There are 11 third basemen in the top 50 alone, and there are four more in the top 80.

More than half of the teams in baseball have one of the game’s 100 most valuable players starting at third base every day. That depth seems to be at least partially attributable to the nature of the position, where typically productive hitters are also providing value on defense.

“Years ago, it was a different position,” Sandoval said. “But now, how many great third basemen we have, it’s now both sides.”

At his best, Sandoval provided that all-around impact. Despite his large build, defensive metrics were often favorable during his time in San Francisco, and he hit enough to make two AllStar teams and once finish top 10 in MVP voting.

If he once represented the upside of the position, though, Sandoval’s now the poster boy for the Red Sox struggles. Since signing a five-year, $95 million contract before the 2015 season, Sandoval’s played only 146 games, hit just .238 and had the worst defensive metrics of his career — a combination of injury and poor performance that has haunted the Red Sox at a position where the rest of the league seems to thrive. Kris Bryant, Manny Machado and Nolan Arenado are widely regarded as three of the best young stars in the game, Miguel Sano and Eugenio

Suarez are having breakout seasons, Justin Turner, Jose Ramirez, Anthony Rendon and Jedd Gyorko are perhaps underrated performers for playoff contenders, and Evan Longoria and Chase Headley are veterans putting up solid numbers within the American League East.

That’s to say nothing of versatile Josh Harrison, Beltre’s replacement Joey Gallo, and home run hitters Jake Lamb and Travis Shaw.

With so much league-wide depth at third base, who’s having as much trouble at the position as the Red Sox? The Mets have tried to use Jose

Reyes at third, but he has as many errors as stolen bases, largely because he’s hitting below .200 and rarely getting a chance to run. They’re beginning to move on to other options.

The Phillies seem committed to 24-year-old Maikel Franco, but his offensive numbers are nowhere near what they were the past two years.

The Giants have moved struggling Eduardo Nunez into more of a utility role, opening third base for prospect Christian Arroyo, who’s been underwhelming. The Braves continue to use

Adonis Garcia, even though his -0.5 WAR is among the lowest of any lineup regular in the Majors.

Even the White Sox have had trouble at third base because Todd

Frazier is hitting below .200 without nearly the 40-homer power he showed last year.

So, the Red Sox are not alone in having a hard time finding a productive third baseman, but they’re definitely in the minority.

Rockies’ surprising climb

A quarter of the way through the season, the Red Sox are hardly the only 2016 playoff team having a hard time gaining an advantage in 2017. Of the 10 teams that went to the postseason last year, only the Nationals are leading a division this year.

The best team in baseball has been the Astros — a third-place team last season — but in terms of division-leading shock factor, it’s hard to top the Rockies. They’re challenging the Nationals for the best record in the National League, and if they keep this up, the Rockies would have their first winning record in seven years and their first division title in franchise history.

Remarkably, the team that plays in homer-friendly Coors Field is being led by its pitching staff.

The Rockies had the worst team ERA in baseball three of the past five years, and when they weren’t in the cellar, they ranked 28th in 2013 and 27th last year.

Little coincidence that, as they’ve moved to the top of the division, the Rockies have also moved up to 20th in team ERA this season with a 4.31 mark through 40 games, more than a half-run better than last year.

Their team OPS is lower than last season, and the Rockies don’t lead the National League in runs scored as they did last year, either. But pitching has carried them.

Certainly it’s helped that former Royals closer Greg Holland has revitalized his career, locking down the ninth inning after missing all of last season while recovering from Tommy John surgery.

The real difference maker, though, is Colorado’s rotation, which is the youngest in baseball and has thrived despite being without ace Jon Gray for all but the first two weeks of the season.

“I like these guys, because they don’t scare off,” new manager Bud

Black told the Denver Post.

Don’t forget about Sam

The Pawtucket arrival of David

Price and Sandoval on rehab assignments made Friday night the highest-profile moment of the year for Triple-A PawSox. But it’s worth also noting what happened one day earlier. PawSox first baseman Sam Travis had five hits Thursday. It was his fourth straight multi-hit game, and his seventh multi-hit game in the past 10.

Rated as the Red Sox’ fourthbest prospect by Baseball America, Travis has raised his batting average more than 100 points since late April, reasserting himself as the organization’s top young Triple-A talent.

Speaking of which: Baseball America has updated its list of Top 100 prospects to reflect early season performances, and to eliminate players who now have too many Major League at-bats to fit their prospect label, such as Red Sox outfielder Andrew Benintendi.

The update has been kind to Red Sox third baseman Rafael Devers, who’s already one of the top power hitters in Double-A at age 20. Baseball America now ranks him 14th in all of baseball, four spots higher than when the season started. Lefty starter Jason Groome went from No. 43 to 41 despite being hurt for all but one start this year. Former Red Sox prospect Yoan

Moncada — traded to the White Sox in the Chris Sale deal — is now No.1 on Baseball America’s list. Benintendi was No. 1 when the season started.

The kids are all right

Despite their difficulties at third base this season, the Red Sox have resisted the urge to fast-track Devers from Double A to the big leagues, but not every team has been so patient.

Just last week, the Red Sox were in St. Louis, where injuries and a crowded 40-man roster forced the Cardinals to rush center fielder

Magneuris Sierra straight from High A to the majors. The 21-yearold old responded with a hit in each of his first seven games; 11 hits in all, all of them singles.

But Sierra’s leap is nothing compared to Allen Cordoba. The Padres are carrying three Rule 5 picks, two of which hadn’t played above Single A before this season. Cordoba was the least experienced of the bunch, having never played above rookie ball before the Padres put him on their Opening Day bench.

Through his first 54 at-bats, though, Cordoba has hit .278 and slugged .481 with three home runs while playing shortstop and left field with a few innings at second base and center field.

According to the San Diego Union Tribune, while making a double switch in late April, Padres manager Andy Green told the home plate umpire: “I’m leaving the kid from the Appalachian League in for defensive purposes in front of 40,000 fans.”

Just checking in . . .

Odds and ends along the trail with the Red Sox:

• When the team made its two biggest trades of the offseason, the headline names were Moncada for Sale and Shaw for Tyler

Thornburg. Moncada and Shaw have thrived — and certainly, so has Sale — but so, too, have the secondary pieces the Red Sox surrendered. Flamethrower Michael Kopach has 51 strikeouts in 351⁄ innings for the White Sox’ 3 Double-A affiliate, and middle infielder Mauricio Dubon is hitting .314 with a .371 on-base percentage through his first 40 games in Double-A with the Brewers.

• Had he not been claimed off waivers by the Red Sox, it’s unlikely Steve Selsky would have found much more opportunity sticking with the Reds. While the Sox have Selsky stuck in Triple A, the Reds have gotten an .800-plus OPS from first baseman Joey Votto and both corner outfielders, Adam Duvall and

Scott Schebler — all players who would have been ahead of Selsky on the depth chart. Votto’s been especially good, flirting with the fourth OPS of 1.000 or better in his career.

• With the Red Sox in town last week, Derrick Goold of the St. Louis Post-Dispatch looked back on the 2014 trade that sent

Joe Kelly and Allen Craig to the Red Sox for John Lackey and a pitching prospect. The lingering impact for each side is limited, but Kelly remains a valuable part of the Red Sox bullpen, Craig is a costly part of the payroll stashed in Triple A, and the Cardinals have the benefit of a standout prospect acquired as draft compensation when Lackey became a free agent.

Most any analysis seems to favor the Cardinals.

“All around it was a good trade,” Kelly told Goold. “Lackey pitched well here. Right now, I’m in the bullpen trying to put some good innings in there, trying to help us win.”