"You see the talent, but until you get the chance to see somebody day in and day out ... he's got all the tools," Pelfrey said.
Garcia showed those off Saturday night, hitting two home runs and two doubles and driving in a career-high six runs to lead the White Sox to a 16-1 victory against the Seattle Mariners at Safeco Field.
"As big and strong as he is, there might be a couple more multi-homer games," said Pelfrey, who pitched six innings of four-hit ball to earn his first victory of the season.
The first eight hitters in the Chicago batting order each had at least two hits, and all nine White Sox batters had at least one hit and one RBI.
It got so bad for the Mariners that manager Scott Servais sent utility infielder Mike Freeman to the mound to pitch the ninth. Freeman allowed three consecutive singles to open the inning but allowed just one run on a sacrifice fly by Willy Garcia.
Pelfrey (1-4) didn't walk a batter and struck out three. The only run he allowed came after the White Sox built a 10-0 lead.
"Sometimes as a pitcher, you get that many runs and might let down a little bit, and he stayed very focused, gave us six good innings," White Sox manager Rick Renteria said.
Seattle's Yovani Gallardo (2-4) struggled from the start.
The White Sox scored four runs in the first before Gallardo could record an out, although that wasn't entirely his fault.
After Yolmer Sanchez led off with a walk, Melky Cabrera grounded a ball to Freeman, who was getting a start at second base with Robinson Cano on the disabled list. Freeman bobbled the ball, then stumbled while trying to tag out Sanchez between the bases. The error resulted in runners at first and second.
Jose Abreu smashed a run-scoring double down the left field line to open the scoring. Avisail Garcia followed by hitting the first pitch he saw for a three-run homer to left field, making it 4-0.
He homered again in the third, his eighth of the year, to make it 5-0.
"When you focus, good things happen," Avisail Garcia said. "Just tried to stay in the middle and trust my hands."
Said Renteria: "That was pretty impressive. I think he's been having really good at-bats and he's driving the ball. ... We're very hopeful that he's breaking through."
The White Sox knocked out Gallardo in the fourth. They loaded the bases with no outs before a sacrifice fly from Willy Garcia. Sanchez's single down the left field line loaded the bases again, and Cabrera hit a two-run double to left field to make it 8-0.
Abreu flied out to the deepest part of center field, bringing Servais to the mound to relieve Gallardo before he had to face Avisail Garcia a third time.
"Not a good start at all," Servais said. "Fortunately, it only counts as one loss."
Avisail Garcia greeted left-hander Dillon Overton with a two-run double into the gap in left-center field to give Chicago a 10-run lead.
Gallardo wound up charged with 10 runs (nine earned) on nine hits and two walks in 3 2/3 innings. He struck out four.
Seattle catcher Carlos Ruiz led off the sixth with a double into right-center field and scored on a pair of groundouts.
Chicago scored five more in the seventh off Overton to make it 15-1.
NOTES: White Sox starting pitchers were 0-8 with a 5.75 ERA over the previous 13 games before RHP Mike Pelfrey snapped the streak Saturday. ... Chicago 2B Yolmer Sanchez extended his hitting streak to 11 games, going 2-for-5. ... The White Sox reportedly reached an agreement with prized Cuban OF prospect Luis Robert, 19, on a deal worth more than $25 million.