Both were limited in their appearances Tuesday preparing for the Solheim Cup.
Pettersen, 36, walked some holes at Des Moines Golf and Country Club, but she didn’t hit any full shots, limiting herself to putting.
“She’s dealing with a little bit of a sore back,” European Solheim Cup captain Annika Sorenstam told Golf Channel’s Chantel McCabe in a Golf Central interview. “She wants to take it easy. Better to be safe than sorry.”
Pettersen did not attend a scheduled news conference.
Notably, European vice captain Catriona Matthew practiced as an alternate Tuesday.
“While there are no immediate injury concerns, Catriona was practicing with the team today as a precautionary measure,” Sorenstam said in a statement.
Pettersen has dealt with back problems through her career. She withdrew from the 2014 Kraft Nabisco because of a back injury, and she played just nine LPGA events back in ’05 because of back problems.
“Fortunately, we have some good physios . . . and Suzann has a fighting spirit,” Sorenstam said.
If Pettersen or another European were unable to play, Matthew, 47, is designated as the alternate to step in.
The Europeans are also dealing with Anna Nordqvist’s bout of mononucleosis. Nordqvist played through the Ricoh Women’s British Open with it two weeks ago, but it’s still a potential issue.
“Just not pushing it too hard,” Nordqvist said. “Walking up some hills, you have to take a few extra breaths, because I was a little more tired than normal. It's been an interesting last few weeks, but I'm definitely feeling better and I'm excited to be here.”
She’s hopeful she can play 36 holes in a day.
Thompson, 22, practiced Tuesday but did not attend a scheduled news conference.
“Unfortunately, I’ve been battling an illness for the past few days and am having difficulty sleeping,” Thompson said in a statement. “I have been advised to focus on getting some rest in order to make a full recovery. I’m looking forward to getting healthy and having an amazing Solheim week.”
U.S. captain Juli Inkster designated Paula Creamer as her alternate this week. When Jessica Korda withdrew with a left forearm injury last week, Creamer took her spot on the roster. Inkster then submitted another player’s name as alternate, though the new alternate hasn’t been identified.