It was quite a week, watching the emergence of 21-year-old Magneuris Sierra in a Cardinal uniform, causing havoc with the opposition at the plate, on the bases and in the field.

While Sierra has been terrific in his six games, with a .375 average, a .423 on base percentage and seven runs scored, there’s more on the way from the Cardinal system. He was only their seventh ranked prospect by MLB, and several more youngsters have emerged since the start of the season.

Here’s a six pack of minor league information…

1) While top prospect Alex Reyes is in St. Louis rehabbing from Tommy John surgery, number TWO prospect Carson Kelly is tearing it up at Memphis. The former minor league Gold Glove winning catcher is hitting .323 with seven doubles, five homers and fifteen RBI for the Redbirds. He’s got a .411 OBP and a .970 OPS. Pretty soon, Kelly will have done all he can at the minor league level and the Cardinals will have to figure out what to do with him.

2) The starting pitching in the system has been outrageous. Number three prospect Luke Weaver was shut down with a back injury on opening day, but has returned with a vengeance. The Memphis righthander was the PCL player of the week for the first week in May, and in three starts since coming off the DL is 3-0 with eighteen strikeouts and thirteen hits allowed in twenty innings. Weaver was disappointed to give up a run on Saturday, his first of the season making his ERA 0.41.

Number eight prospect Jack Flaherty is at Springfield, where he’s already 6-0 with a 0.99 ERA and 45 strikeouts in 45.1 innings. He’s allowed thirty hits and walked six, and in seven starts has yet to allow more than two earned runs (which he has done once). Number ten Junior Fernandez tossed a complete game for Palm Beach last week, allowing one run on five hits against Fort Myers. The 20-year-old needs to become more consistent. He’s allowed zero runs or one run in three starts, and five earned runs in two. In his other start, Fernandez allowed three.

3) The trickle down from the Tommy Pham promotion to the Cardinals has been interesting. When Pham joined the Cardinals, Nick Martini was called up from Springfield to Memphis. With the Redbirds, Martini has hit .448 with a 1.170 OPS in 32 plate appearances. Martini has four doubles and a triple for Memphis. At Springfield, 25-year-old Thomas Spitz replaced Martini, and that may be where Sierra goes when Jose Martinez and Stephen Piscotty are healthy.

Memphis has Martini joining Harrison Bader and Todd Cunningham. Springfield has Cuban import Jose Adolis Garcia and 2013 second rounder Oscar Mercado in the outfield. Mercado is hitting .326/.396/.512 and has thirteen extra base hits for the Cardinals, so he isn’t going anywhere. Sierra could easily replace Spitz or Blake Drake in the Springfield outfield, though.

4) The Cardinals’ international signings, who are extremely young, inexperienced and raw, are off to slow starts. Jonathan Machado is in the Dominican Summer league, where the eighteen-year-old is hitting .209 with a .284 OBP. Eighteen-year-old righthander Johan Oviedo has a 1.66 ERA in seven games in the same league. 22-year-old Cuban Randy Arozarena is hitting .202 at Palm Beach. We should all take these numbers with a grain of salt.

5) The Cardinals had some kids perform well in spring training. Harrison Bader hit .346 with a 942 OPS. So far at Memphis, he’s hitting .279/.358/.484 with seven doubles and six home runs. Shortstop Paul DeJong showed well early in spring with a couple of home runs. Right now at Memphis he’s hitting .293 with a .318 OPB, but eight homers and 23 RBI. 40-man roster second baseman Breyvic Valera hit .304 in 23 spring at bats, and has a .764 OPS with the Redbirds.

The other impressive minor league hitter in spring training was Patrick Wisdom, who it .304 with five extra base hits in 30 at bats. The third baseman has an .855 OPS in 136 plate appearances, with eight doubles, a triple and five home runs.

6) Much was made of the Cards having four of the top 70 picks in last year’s draft. How are they doing? Shortstop Delvin Perez, already the club’s fourth ranked prospect, is hitting .294 with a .354 OBP in the Gulf Coast league. He has 48 hits (eight doubles) with a dozen walks and a dozen stolen bases in 163 at bats. By all accounts, Perez is already playing a near MLB quality defense. Eighteen-year-old center fielder Dylan Carlson was the Cards’ second first rounder last year. He’s at Peoria, hitting .214 but has a .340 OPB. At Peoria, he’s been thrown into some deep water early but is responding.

Third first rounder Dakota Hudson, a 22-year-old righthander from Mississippi State, is at Springfield and is finding his way. He sports a 3.41 ERA with 31 strikeouts in 35.1 innings. Hudson needs better command…he’s walked eleven already…but after a brilliant start last season, the Cardinals have high hopes. Finally, second rounder Connor Jones, a 22-year-old righthander from Virginia, is 2-2 with a 5.75 ERA at Palm Beach.

Sierra is fun, but it looks like the Cardinals have a few more guys to join him here in St. Louis. Marco Gonzales is set to rejoin the Memphis rotation after two years of injuries, and John Gant, acquired from Atlanta in the Jaime Garcia deal, isn’t far behind. And the Cardinals have a legitimate shot at soon-to-be free agent Cuban outfielder Luis Robert, a nineteen-year-old who becomes free this week.

After a down season, the Cardinal farm system has rebounded, and there’s a lot more to look forward to from that pipeline in the coming months and years.