Nieves pulled up lame while running to second base on a double Wednesday. Nieves said afterward that he felt a pop in his right quadriceps.
"They said it was mild, and usually I'm a quick healer, so hopefully that's the case," said Nieves, who hoped to avoid a stint on the 15-day disabled list.
Rupp's arrival at least gives the Phillies protection behind the plate should something happen to Carlos Ruiz. Rupp, the team's 18th-ranked prospect, impressed in four games late last season, but he was hitting just .167 with a .665 OPS in 129 plate appearances with Lehigh Valley.