The A's have been quiet this offseason. After losing in the AL Wild Card Game the last two seasons, they have their eyes set on winning the division and having an easier road to the World Series.

There really is a method to their madness, too.

Why haven't the A's made any big moves this offseason? Because they're focused on keeping their core of young stars together for the long term. In the near future, that will start with shortstop Marcus Semien, who is a free agent after next season and is expected to earn nearly $14 million in arbitration this offseason.

But right behind him are two homegrown stars in Matt Chapman and Matt Olson. MLB.com listed Chapman as Oakland's best prospect success story of the decade, and they're not wrong. However, Olson isn't far behind.

Looking at Baseball America's list of A's top prospects for the 2010s mostly is nothing more than a sight for sore eyes. Need proof? Here you go.

2010: Chris Carter

2011: Grant Green

2012: Jarrod Parker

2013: Addison Russell

2014: Addison Russell

2015: Daniel Robertson

2016: Franklin Barreto

2017: Franklin Barreto

2018: A.J. Puk

2019: Jesus Luzardo

The best of the bunch are the last two names. Puk and Luzardo -- whom the A's acquired in a trade with the Washington Nationals in July 2017 -- made their MLB debuts last season and look set for stardom. They are two of the best left-handed pitching prospects in baseball and can lead the A's rotation next season.

Chapman and Olson both are former first-round draft picks by the A's, and clearly it was a mistake by Baseball America to never have them atop the team's top prospects list. Oakland took Olson with the No. 47 overall pick in the 2012 draft before selecting Chapman at No. 25 two years later.

Since they made their respective big league debuts, the two Matts have been two of the best players in baseball.

Olson had a short 11-game stint with the A's in 2016 before breaking out in 2017. The powerful first baseman had 23 homers in 79 games in Triple-A for the Nashville Sounds. Somehow, he was even better with the A's.

The 6-foot-5 lefty smashed 24 long balls in just 59 games with the A's as a rookie. He had a .651 slugging percentage and 1.003 OPS. Since then, Olson followed his rookie year with seasons of 29 and 36 homers.

Olson has 89 homers and an .862 OPS the last three years for the A's. He also been one of the best defensive first basemen in the league, winning a Gold Glove the past two seasons. The 25-year-old has been worth 12.2 bWAR from 2017 to '19.

And yet, Chapman has been even better.

The A's finally have their Josh Donaldson replacement. Chapman debuted for the A's as a 24-year-old in June 2017. He wound up hitting 14 homers in 84 games and gave fans a glimpse of his jaw-dropping defense,

Even though he didn't come up until halfway through'17, Chapman has been worth an absurd 18.5 bWAR. For comparison sake, Donaldson was worth 16.7 bWAR his first three full seasons with the A's.

Chapman already has finished in the top-seven of AL MVP voting twice, won two Gold Gloves and made his first All-Star team last season. At the plate, he has gone from 14 homers as a rookie to 24 in 2018 and 36 in 2019.

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Like any team, the A's have swung and missed with a handful of prospects. When it comes to Chapman and Olson, though, they couldn't have asked for anything better.

Now, they must keep these two stars in Oakland.