DeChambeau had previously been linked to the breakaway circuit but said in February that "as long as the best players in the world are playing the PGA Tour, so will I".
Dustin Johnson also said he was "fully committed" to the PGA Tour on the same day, but he subsequently resigned his membership and is competing in the opening £20milion LIV Golf event at Centurion Club this week.
Minutes after the first shots were struck on Thursday, the PGA Tour suspended all 17 players in the field who were taking part despite having been turned down for the required releases.
PGA Tour commissioner Jay Monahan added: "The same fate holds true for any other players who participate in future Saudi Golf League events in violation of our regulations."
After missing the cut in the Masters, DeChambeau underwent hand surgery and returned to action with another missed cut in last week's Memorial Tournament, where he was asked if the injury had affected his decision-making regarding the LIV Golf league.
"For me, I personally don't think that at this point in time I'm in a place in my career where I can risk things like that," the big-hitting American said. "I'm loyal to my family that I've created around me with sponsors and everything."
One of DeChambeau's sponsors, Rocket Mortgage, immediately ended its relationship with the 28-year-old American when his imminent move to LIV Golf was reported.
LIV Golf CEO Greg Norman, who is expected to sign more players ahead of the second event in Portland, Oregon from June 30 to July 2, said: "Bryson DeChambeau is an exciting addition to LIV Golf's supercharged style of play.
"He is passionate about the sport, innovative in his approach and committed to pushing the boundaries in pursuit of excellence."
South Africa's Branden Grace welcomed the addition of DeChambeau and believes the PGA Tour could be forced to change its stance if more and more players sign up.
"You would think so," Grace said. "But I really don't care what they do. I resigned my membership so this is the decision I've made. It was a great opportunity I felt I could not let slip."
The DP World Tour has yet to make any comment on how they will treat the rebel players, with two-time major winner Martin Kaymer expecting they will wait until the current mixed event in Sweden finishes on Sunday.
Kaymer and Sergio Garcia remain on the entry list for the BMW International Open in a fortnight's time and Kaymer said he had not heard anything to suggest he would not be allowed to play.
"I haven't heard anything. I'm planning to play in Munich," he said.
On the course, former Masters champion Charl Schwartzel remains in pole position to claim the first prize of 4million US dollars on Saturday after adding a 66 to his opening 65 to reach nine under par, three shots clear of Hennie Du Plessis.
The South African pair are both part of Stinger Golf Club in the four-man team event, meaning they hold a seven-shot lead and are on course to share another 3million US dollars.
Six-time major winner Phil Mickelson, who is playing his first event since February, struggled to a second round of 75 to fall 13 shots off the pace.