PEORIA, Ariz. -- After a breakout 2018 in which he led Yankees farmhands with 70 walks and placed second with 21 homers, Brandon Wagner slumped terribly this year. He hit just .179/.290/.280 with eight homers and posted the fourth-worst batting average among Minor League full-season qualifiers.

New York gave Wagner a chance for redemption by sending him to the Arizona Fall League and he's making the most of it. He's hitting .259/.429/.556 with two homers through eight games with the Surprise Saguaros, leading the developmental circuit with 15 RBIs and ranking second with seven walks. The AFL named him the Championship Chains Player of the Week for games of Sept. 23-29, during which he went 5-for-13 (.385) with a pair of grand slams and 11 RBIs.

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Both slams came against Peoria left-hander Osvaldo Fernandez (Padres), and the second one capped a seven-RBI game on Sunday.

"I can't remember a seven-RBI game," said Wagner, a 24-year-old first baseman. "I don't think I've ever hit two grand slams in a week. I hit one this year but never two in a week."

The Yankees selected Wagner in the sixth round of the 2015 Draft after he batted .435/.571/.891 at Howard (Texas) JC and ranked among the national juco leaders in runs (86, second), on-base percentage (second), homers (22, third) and slugging (seventh). His left-handed power played in the lower levels of the Minors but he has struggled since advancing to Double-A in late July 2018.

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Wagner attributes his difficulties to getting away from his true self at the plate. He said his main goal in the AFL is to regain his confidence.

"In 2018, I remember being pretty aggressive, especially in hitter's counts," he said. "This year, I was just kind of falling behind and being too passive. So out here, I'm trying to be more aggressive, swinging at the pitches I want to swing at, trying to do damage."