The shortstop originally signed for $375,000, and now he might be the best in the league. The third baseman signed for $50,000, and now he might be the Rookie of the Year.

These are the kinds of stories baseball people love, and the San Francisco Giants have an infield full of them. They have four homegrown starters that cost them not even $2 million in combined bonuses, and they may well have the best four-man unit in the game.

From first baseman Brandon Belt to second baseman Joe Panik to shortstop Brandon Crawford to third baseman Matt Duffy, they’re all good and getting better. They’re all young and under control. And if you add in catcher Buster Posey, also homegrown (although not signed on the cheap), they give the Giants reason to believe that this run of championships could last.

They’re not done this year, even after a lost weekend at Wrigley Field. They need to get Panik back healthy (he’s on the disabled list with a lower back strain and could return next week), and they need to get Mike Leake healthy (on the DL with a hamstring strain).

But it’s not at all crazy to suggest, as Giants pitcher Jake Peavy did Sunday (via John Shea of the San Francisco Chronicle), that “this is a better ballclub than [the Giants] had last year.”

Last year’s Giants, as you may remember, won the World Series.

The Giants have won three times in five years, and it’s no longer newsworthy to say that they know what they’re doing. What is interesting is that after first winning because they did a better job than anyone at drafting and developing pitching, the Giants now have a chance to keep winning because they’ve been better than anyone at finding quality infielders.

Belt and Crawford have already been part of two championships, but Belt is 27 and Crawford is 28. Panik and Duffy, who contributed last October, are both just 24.

This season, all four have an OPS above .800 and an OPS+ of 128 or better, per Baseball-Reference.com, meaning that each has been about 30 percent better than average.

“And defensively, they’re like a bunch of Hoover vacuum cleaners on the infield,” said one rival scout who sees the Giants regularly.

It’s fun to hear scouts rave about the Giant infielders now because so many scouts missed on them in the past. Duffy was an 18th-round draft pick, Crawford a fourth-rounder and Belt a fifth-rounder. The Giants took Panik with the 29th pick overall in 2011, but at the time, many outside observers considered the pick something of a reach.

“Our scouts followed these guys for a number of years,” Giants scouting director John Barr said Monday. “They believed in them.”

But even the Giants themselves could be surprised.

Panik didn’t get a chance last season until Marco Scutaro got hurt and the Giants were desperate for help at second base. This year, the Giants signed Casey McGehee to replace Pablo Sandoval at third base and only turned to Duffy when McGehee flopped.

Soon enough, manager Bruce Bochy began batting Duffy third, just in front of Posey. And in a season where the National League is full of talented and touted rookies, Duffy’s Giants teammates have begun making the case that he could be the best of all.

“Duffy has been a ridiculous addition to this club,” outfielder Hunter Pence told Andrew Baggarly of the San Jose Mercury News. “I don’t know how [others are] missing it, because we’re in the middle of the race and he’s doing so much for us. … You’re watching an incredible talent step into the league with Matt Duffy.”

The numbers show it. Baseball-Reference.com credits Duffy with a 3.8 WAR, tied with Pittsburgh‘s Jung Ho Kang for tops among major league rookies. Duffy’s 2015 WAR ranks third on the Giants, behind Posey (5.7) and Crawford (5.4), and just ahead of Panik (3.3) and Belt (3.0).

Not bad for a guy that Baseball America said last winter has left scouts around baseball shaking their heads.

On its list of top Giants prospects, Baseball America had Duffy ranked ninth. That’s right where Panik had been the year before. Neither ever came close to making the newspaper’s list of the top 100 prospects in the game.

In fact, of the four Giants infielders, only Belt made a Baseball America Top 100 list. He ranked 23rd in 2011, the only time he was ranked.

Prospect rankings are nice. Major league performance is better.

With their cheap, productive, young infield, the Giants will take what they have.

 

Danny Knobler covers Major League Baseball as a national columnist for Bleacher Report.

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