Thomas is seeking his fourth victory of the 2016-17 season while world No. 1 Johnson is making his first start since winning the Genesis Open at Riviera two weeks ago.
Brazel is three shots ahead of fellow Australian Marcus Fraser (through 14 holes), who reached three under during his front nine but plummeted to two over after four consecutive dropped shots and a double bogey.
"But on the positive side I had a lot of fun with my brother carrying the clubs as he's so much fun to be around, and he did a great job today". "Starting the day, I would have taken a 65, but I feel like I could have been a few more ahead". Take each day as it comes.
"I tried to approach this week just to see how it went".
Sore ribs or sore stomach, it doesn't seem to matter to Rory McIlroy.
And the four-time major victor was ideally placed to fulfil his part of the bargain after a second round of 65 at Chapultepec Golf Club which left him two shots ahead of Phil Mickelson, Justin Thomas and England's Ross Fisher.
83-year-old is Dallas County's 8th flu death this season
Forty-eight influenza-related deaths have been recorded by the Oklahoma State Department of Health since September of 2016. Officials say residents in Tulsa County has been hardest hit by the flu this season, leading to 13 deaths in that county.
However, it was the sublime expertise of Jordan Spieth on the turf that garnered the spotlight, as the American golfer hit "shot of the day" during round two on Friday. "My body is in great condition and if I keep playing well, I have a chance going into the weekend".
He hit 8 of 14 fairways and 16 of 18 greens in regulation on his way to a course-record 63 that moved him back into contention.
Meanwhile, five-time major victor Mickelson showed few ill effects after being forced to change his caddie at the start of his second round.
His game looked better than ever.
Fortunately, Mickelson's brother Tim was in the crowd who is not only a decent player but is a former golf college coach turned player manager, and is in Mexico with client, Jon Rahm.