DENVER -- A new $9 million contract might have been the cause of Nick Hundley's struggles.

"There's a lot of factors, and I wouldn't exclude that one," San Diego manager Buddy Black said on Saturday, one day after the 28-year-old catcher was optioned to Triple-A Tucson. "He'd probably say [it wasn't], but there's something to that. He takes his responsibility strongly."

Hundley, who signed a three-year deal in the offseason with a club option for 2015, was hitting .166 (32-for-193) with 22 RBIs. However, Hundely had thrown out a Major League-leading 19 would-be base stealers.

Replacing Hundley on the 25-man roster is Yasmani Grandal, who started Saturday's game against the Rockies. Black expects Hundley's time in the Minors to be beneficial.

"We felt it was time to give Nick a breather from the pressure that he's put on himself to perform," Black said. "He's a guy that takes his performance, his contributions, as strong as anybody. When things weren't going his way, things were building up and effecting his performance. So it's a classic case of taking one step back to take two forward."

Peavy makes pitch to aid cancer research

DENVER -- Former Padres pitcher Jake Peavy, now with the White Sox, has announced he will contribute $100 for every strikeout in every Major League Baseball game on Saturday towards pancreatic cancer research, which killed his friend and mentor, Darrel Akerfelds.

Akerfelds lost his 19-month battle with pancreatic cancer last Sunday.

"I do hope there are a lot of strikeouts in baseball today," said Peavy, who started on Saturday against the New York Yankees.

Peavy previously raised more than $52,000 to aid pancreatic cancer research, in Akerfelds' honor.

"Ak knew what the percentages were and he just kept fighting with the thought that today could be the day a cure is found," Peavy said in a statement. "He battled with so much courage and heart, and I will continue to fight until there is an end to all cancer."

Worth noting

• Jeremy Hermida began a rehab assignment with Triple-A Tucson on Friday night and went 1-for-2, starting the game in right field. Hermida (strained left adductor) was placed on the 15-day disabled list April 27 and was extended to the 60-day DL last Monday.

• With pitcher Edinson Volquez starting and Yonder Alonso and Yasmani Grandal in the lineup, Saturday marked the first time three of the four players acquired from Cincinnati in the offseason started the same game. Brad Boxberger, the fourth player, is currently with Triple-A Tucscon, but has a 1.42 ERA in five relief appearances with the Padres this season.