Entering Tuesday's game against the Mets, Guzman, who has primarily played first base since his promotion from Triple-A Tucson on June 16, was hitting .339 and has five home runs and 28 RBIs in 122 plate appearances.
He was slotted third in the order in the second game of a four-game series with the Mets.
Guzman, who took a nine-game hitting streak into Tuesday's tilt, was hitting at a .378 clip and led all Major League players with 24 RBIs since the All-Star break.
Better still, Guzman hit .380 with 24 RBIs in 21 games since July 16.
"He's always hit in the Minor Leagues and now he's shown that, given the extra chance in the big leagues, he can hit here," Hoyer said.
Guzman, 27, was hitting .332 with Tucson before he was promoted. He has played some third base and left field, but has mostly played first base.
That Guzman has been on such a tear at the plate hasn't necessarily surprised the Padres, who signed him to a Minor League contract in November.
Guzman is a career .305 hitter in the Minor Leagues, with a .373 on-base percentage. His only taste of the Major Leagues before this season came in 2009, when he had 20 at-bats with the Giants.
Has Guzman essentially cemented a spot for himself on the 2012 roster? Manager Bud Black said to ask him again the end of the season, when Guzman's sample size is more substantial.
"He's a good hitter, and right now, he's swinging the bat very well, there's no doubt about it," Black said. "Let's keep it going. At the end of the year, let's look at it again.
"Every day is a test and right now, he's passing every test with flying colors."