The projected cut at the weather-affected final major of the season is 147 and Laird and Knox fall just below that mark.
Laird followed his opening 77 with a 72, leaving him on seven-over 149. Knox shot 73 for a two-round total of 150.
Laird had birdies at two, 14 and 18 but stumbled to a double bogey at the third and dropped further shots at the fifth and the 16th.
Knox, whose round was interrupted by the threat of lightning, bogeyed holes one, six and nine but birdied the seventh and picked up further shots at the tenth, 12th and 14th. He came unstuck with a double bogey at the 15th and dropped another shot at the 16th.
Kevin Kisner of the United States and Hideki Matsuyama of Japan are joint leaders on eight under.