Clarke, who oversaw major change at the club over the summer - adding fifteen players to his squad - couldn't hide his disappointment as goals from Ryan Taylor (2) and Antoni Sarcevic saw the Pilgrims take all three points as the new look Reds continued their spell of poor form - picking up a second defeat in three league outings.
The manager named a slightly different line-up from the one which drew with Newport County in midweek as Cameron Pring, James Hardy, and Josh Gordon made way for Callum Cockerill-Mollett, Gary Liddle, and Caolan Lavery, however the Mansfield-born boss wasn't able to secure a better result as goals were once again hard to come by.
Speaking to the assembled media, Darrell said; "For me, the honeymoon period is well and truly over. I am disappointed with the points total of five points from five games.
"It is yet another game where we are looking to change momentum but we don’t do it in the final third - again. I’m frustrated, it wasn’t good enough. We had a lot of the ball, we worked a lot of opportunities, we got into good areas.
"But we didn’t take care of the final pass or final shot - it’s the same again. So we have got to work hard and get back to it on Monday morning and rectify what we need to be worked on - again.
"Everyone can see the areas we have worked the ball in. We have had more possession than Plymouth but possession doesn’t win you football matches. You have got to be ruthless in the box, with your run, with your reaction with your final ball.
"All those bits and pieces and your finish - and until we start getting that right it’s going to be a long season. It’s disappointing, it’s all very well being confident and doing it in training - but you have to do it on the big stage. And in the last couple of games we haven’t done that."