Cal notes: Peterson earning high praise

This year's High Desert Mavericks squad features some top-shelf talent in the Seattle Mariners farm system -- namely, No. 2 prospect D.J. Peterson and No. 10 prospect Gabriel Guerrero.

Drafted 12th overall by Seattle in 2013, Peterson started in the Cal League this year after splitting time between Everett and Clinton during his rookie campaign. Through 42 contests this season, Peterson was batting .275/.323/.478 with eight homers and 37 RBIs, 43 strikeouts and 11 walks. This past week he belted three homers and a double while driving in seven runs during a four-game set against the Bakersfield Blaze.

Take a look at Peterson's game log and you'll see a steady stream of production since Opening Day. In fact, the 22-year-old has never had consecutive hitless games in 2014, but it's clear the budding slugger has high standards for himself.

"I think at first it was a little bit overwhelming for him -- his personal expectations, the organization's expectations," Mavericks manager Eddie Menchaca said. "I think that at some point he felt like he was struggling, but he really hasn't. … That's just the type of guy he is."

If Menchaca remembers correctly, something clicked for Peterson in mid-April during a home contest against the Lancaster JetHawks. In a 2-for-14 mini-slump entering the game, the right-handed-hitting Peterson belted a double to the right-field gap and told Menchaca it was his best at-bat as a Maverick once he returned to the dugout.

"You could see that's a guy who's going to get back on track just because of what he did that AB," Menchaca said. "It kind of started to make him understand, 'Hey, this is what I need to be doing.' Once he bought into that, he started to see his batting practice that way. Next thing you know, it started to take over his at-bats in the games."

Though Peterson, 22, has played six games at first base this year compared to 30 at third base, Menchaca said that's more a result of having one true first baseman, Jordy Lara, on the roster.

Like Peterson -- whose brother, Dustin, was selected in the second round in 2013 by San Diego and is the team's No. 15 prospect -- Guerrero has baseball in his bloodlines. His uncle, Vladimir, was a nine-time All-Star and the 2004 American League MVP.

"He takes after his uncle, who swung at balls anywhere and could barrell baseballs," Menchaca said. "Gabby has a bit of that, but he understands his mission and his strike-zone awareness and when to be more aggressive on fastballs. And he's not missing them."

Menchaca coached Guerrero at Class A Clinton last year and said the outfielder finished the season strong before carrying that into 2014. Through 49 games, Guerrero leads his team in batting, posting a .328/.376/.488 slash line with six homers, 33 RBIs, 49 strikeouts and 15 walks.

"Last year I had him hitting in the sixth, seventh hole," Menchaca said. "Now he's my fourth hitter. That should tell you."

Guerrero has a ways to go before he can become a Gold Glover like his uncle, but Menchaca noted that the 20-year-old has a cannon in right field.

"He can always get better at his accuracy," Menchaca said. "But for sure, he's got a good arm. He's a typical right fielder that you'd want in the big leagues."

In brief

Going deep: Top Astros prospect Carlos Correa seems to have found his power stroke for Lancaster. In six games against Bakersfield and Inland Empire, Correa went 8-for-27 with two homers and six RBIs to boost his season slash line to .314/.379/.471 with four homers, 39 RBIs and 10 stolen bases.

Ring 'em up: Ben Lively continues to dominate the Cal League for Bakersfield. Through 10 starts, the right-hander and No. 12 Reds prospect was tied with Dunedin's Taylor Cole for most strikeouts at the Class A Advanced level with 73. Lively is 8-1 with a 1.03 ERA, 0.74 WHIP and just nine walks in 61 innings.

Back to the DL: The San Jose Giants placed right-hander Joan Gregorio, 22, on the disabled list Friday with back soreness after he made one relief appearance following a three-week stint on the DL. The No. 12 Giants prospect is 2-2 with a 6.75 ERA and 1.77 WHIP in five starts this this year.