The 23 year-old clipped in an early opener before John Sweeney's penalty sent United crashing out of the competition to lower league opponents for the fifth time in seven seasons. While happy to make his mark, McManus, a former Scotland youth internationalist, believes his best is yet to come - and he would love to turn on the style when his famous uncle comes to have a look.
Barry Ferguson's latest recruit is the nephew of a certain Walter Smith and McManus said: "I think he'll be coming to a few of our games and hopefully by that point I'll be fully fit as he's probably my biggest critic.
"He's been really good to me over the years with bits of advice, it will be great if he comes to see me play."
McManus, whose career has been hampered by injuries, showed few signs of rustiness as he latched on to Kevin Watt's cross in eight minutes and neatly lifted the ball over David Hutton. Clyde doubled their lead before the break when Scott Ferguson was tripped in the box by Nicky Devlin and Sweeney converted the spot kick.
Clyde eased off after the break, a lapse which earned a rebuke from Ferguson, but still ran out deserved winners. "I'm still trying to catch up with the boys in terms of fitness, but I'm feeling pretty sharp and obviously needed to get a first goal and I want to get many more," said McManus. "I'm looking to give it a real go this season. The gaffer put a lot of faith in me by starting me today and signing me in the first place was a leap of faith."
Rather than showering his players with praise, Ferguson proved that he will be a hard task master in his new role by demanding higher standards.
"We're still really only midway through pre-season so there is room for improvement," he said. "We were poor in the second half and the players have had a rollicking for that because we took our foot off the gas."