Alan Curbishley rued the injury to debutant Matthew Upson following West Ham's 1-0 defeat to Aston Villa.
The defender was substituted in the 30th minute after landing awkwardly, and Curbishley has confirmed that he suffered a calf problem.
Lucas Neill also suffered an injury on his first Hammers appearance last week and Curbishley admits it is frustrating to see lightning strike twice.
"He's done his calf," Curbishley told Sky Sports. "He's gone up to head the ball just near the channel and just got nudged, and as he's landed he's done his calf.
"I thought he was looking quite commanding.
"We signed Lucas Neill last week and he lasted about 20 minutes and I think Matty's lasted just a little bit more, so that perhaps sums us up at the moment.
"I'm hoping that one or two will get back soon, but we'll have to see for next week."
The Hammers fell behind when John Carew pounced for Villa in the first half, and could not force an equaliser despite a late rally.
They are now five points from safety and Curbishley knows the next two games, against fellow strugglers Watford and Charlton, could prove decisive.
"I'm very disappointed with the goal. I didn't see too much danger when Carew picked up the ball. I think it's a soft finish for us," he explained.
"We laid siege near the end but their keeper's pulled off some great saves.
"We need some three-pointers. A point would have been nice and it would have been a confidence booster but we need to win some games and we certainly need to win the next two.
"We've had a terrible week and we're very disappointed but we've got to keep going because the opportunities are there."