Scotland could pay a price for their opening win under new coach Vern Cotter after three players suffered injuries against the United States in muggy Houston.
With a shortage of players on tour, Cotter could find himself having to fly out replacements from home following his team's 24-6 victory.
Centre Duncan Taylor pulled a calf muscle, lock Jim Hamilton turned an ankle and prop Geoff Cross damaged rib cartilage to add to the list of problems that also saw Stuart Hogg, scorer of the final try, go off with a damaged nose that is not expected to keep him out of next week's game against Canada.
Cotter said of his team's effort: "We are happy to get a win in difficult conditions. We showed good structure in the first part of the first half and gave ourselves opportunities to score tries.
"Our scrum got the better of their scrum, which gave us an area to get a good grip of the game and gave us points as well. That was pleasing.
"I'm pretty pleased to see the opportunities created and we will be working on how we get over the line and score more points. We scored three tries and didn't get one scored against us, so it is a good basis to work from.
"They didn't give up and put us under a bit more pressure in the second half. We put them under pressure in the line-out and scrum and they did not get a lot of possession to launch their plays. Unstructured, they were effective, but our defence kept its form and shape and we managed to keep coming up off the line even late in the game."
Tim Visser and a penalty try provided Scotland with their other scores.
The positive feeling presented by Cotter was echoed by captain Greig Laidlaw, who felt frustrated by some of the try chances squandered but generally satisfied.
"The most important thing to come out of the game was that we were not scored against," Laidlaw said.
"It was important to put a marker down in the first game of a tough tour, We probably left a couple of tries out there but we did get out there and did our talking on the field.
"It was tough, we are not used to playing in heat like this. The ball was incredibly slippery - it was a dry night but the ball was slippery and we coughed up a couple of chances and a couple of balls in open play and that destructured the game a bit."
For the Americans, it was a frustrating experience.
"The game never really picked up any momentum, certainly from our side," said coach Mike Tolkin.
"It was very stop-start. We were too aggressive where we should not have been and gave away stupid penalties early on and were not aggressive where we needed to be. Overall we did not do a good enough job holding onto the ball. Opportunities were there, but it was too much stop-start and not enough continuity."