The 23-year-old right-handed reliever dominated Class A Advanced and Double-A en route to a Minor League-leading 38 saves and a 1.86 ERA, earning him the San Francisco Giants' No. 3 prospect ranking.
Now in just his second full season in the Minors, Hembree finds himself closing games for the Fresno Grizzlies, but this season has not been nearly as easy as 2011.
"I still attack the hitters the same way," said Hembree, who is 1-1 with a 4.42 ERA and eight saves in 19 games. "I would still like to be (more) consistent. I've been getting myself in trouble.
"I just want to attack the zone and be aggressive. Obviously the hitters are better here. But I feel like if I can throw my pitches how I want to throw them, I'll be successful."
The first sign of trouble for Hembree came May 14, when he was tagged for five runs -- three earned -- to blow a two-run lead in the ninth inning of an 8-5 loss to visiting Omaha.
Things did not get much better for Hembree in the thin air of Albuquerque. He gave up a towering solo home run to the Isotopes' Brian Cavazos-Galvez in the eighth inning of a 3-2 loss May 21. Hembree then walked two and gave up an RBI triple to veteran Aaron Miles in the ninth inning of a 10-7 win May 23.
"He's got a good arm," Isotopes manager Lorenzo Bundy said. "Obviously command is an issue with him, but it's a pretty good arm."
Hembree's ERA has nearly doubled from the 2.08 mark he had before the meltdown against Omaha, but the South Carolina native said he will continue to approach the game the same way.
"You've still got to attack and pound the zone," Hembree said. "You don't want to give up the home runs or the hits, but it's going to happen sometimes. It's a tough league, but I still stick with my game plan and attack the hitters."
Hembree relies heavily on a fastball that averages between 93 and 96 mph, but he knows how his slider and changeup develop will be the key.
"They're coming along pretty good," Hembree said. "I've got a good feel for them right now. I just want to get out there, throw them as much as I can and develop them."
The Giants have a strong record of developing pitchers, including current starters Matt Cain, Tim Lincecum and Madison Bumgarner, plus injured closer Brian Wilson, the man whose job Hembree could eventually take over.
"It's a good organization to play for," Hembree said. "We're all excited to do the job. I'm blessed to be a part of it and I'm looking forward to seeing what the future holds."
Triple Crown chase: Iowa's Anthony Rizzo continues to terrorize PCL pitching, bashing three home runs in his last five games through Saturday. For the season, the Cubs' prospect has a league-leading 17 homers, ranks second with 44 RBIs and is sixth with a .354 batting average. Rizzo also leads the league in slugging (.713) and OPS (1.130).
FedEx delivers: Albuquerque catcher Tim Federowicz is heating up with the New Mexico weather. From May 17 through Saturday, the 24-year-old prospect has hit .371 (13-for-35) with two home runs and 10 RBIs. Federowicz has been durable too, starting 36 of the Isotopes' 50 games behind the plate.
Carried away: Tacoma right-hander Andrew Carraway was merely a 12th-round Draft pick in 2009 out of Virginia. The way he has pitched in the PCL so far, he looks more like a former No. 1 overall selection. The unheralded right-hander has gone 2-0 with a 2.21 ERA in three starts, allowing just five runs on 13 hits and six walks while striking out 11 in 20 1/3 innings.