In the aftermath of the United States' 17½-11½ defeat to Europe, Patrick Reed told the New York Times that he was "blindsided'' by the decision to split him from Spieth, with whom he had a successful Presidents Cup and Ryder Cup record.
Reed called out captain Jim Furyk for sitting him in two matches, not telling him of the split with Spieth and referring to the situation as a "buddy system.''
"That was something that had obviously been talked about in advance,'' Thomas told reporters at the CIMB Classic in Malaysia, where he is competing in the PGA Tour co-sanctioned event this week. "But all I was worried about, what I knew, that I was going to play with Jordan and we were worrying about taking care of our point and taking care of our match.
"It's a team event, and it's a team week, and we're all worried about each other. But that's kind of our thing, is we do our job. Jordan and my job was to go out and get a point, and that's what we were fortunate to at least get three out of four.''
Thomas, playing in his first Ryder Cup, was one of the few bright spots for the Americans. He and Spieth combined to go 3-1 and he also defeated Rory McIlroy in singles.
Reed went 0-2 playing with Tiger Woods before winning his singles match. He lashed out against being split from Spieth, with whom he had gone 8-1-3 over the past four years at the Ryder Cup and Presidents Cup.
"The issue's obviously with Jordan not wanting to play with me,'' Reed told the New York Times. "I don't have any issue with Jordan. When it comes right down to it, I don't care if I like the person I'm paired with or if the person likes me as long as it works and sets up the team for success.
"He and I know how to make each other better. We know how to get the job done.''
Not playing all the matches miffed Reed, who won the Masters this year but has struggled since finishing fourth at the U.S. Open.
"For somebody as successful in the Ryder Cup as I am, I don't think it's smart to sit me twice,'' he said.
Spieth said during a post-match news conference that there were no surprises. Furyk, in an interview earlier this week with Golf Channel, said several of the pairings were set weeks ago.
Thomas, a nine-time winner on the PGA Tour, won his first two titles at the Malaysia event, which is the second tournament of the 2018-19 PGA Tour season.
"It's so easy to look at the captains and say it's their fault,'' Thomas said. "But at the end of the day, we didn't play well enough. The Europeans played exponentially better than we did -- that's why they beat us as bad as they did. It's easy to look at pairings and say, well, we should have done this or we should have done that. But it doesn't matter if you put the two winningest guys of all time together; if they don't play well, they're going to lose.
"Everybody has their own thoughts and feelings, but at the end of the day, we just didn't play well enough.''