Nottingham director of rugby Glenn Delaney was frustrated by his side's sloppiness in Sunday's exciting 33-31 home win over London Scottish.
Nottingham dominated the first half at Meadow Lane to lead 23-6 at the break.
But a disastrous start to the second half meant that the hosts had to come from behind to win.
"To go from a 17-point lead and being in complete control to not being in control is something we have to look at," Delaney told BBC Radio Nottingham.
"At half-time the game was very comfortable, we were performing well and it didn't look like we were in any trouble.
"After half-time we didn't execute the plan we put in place, which was disappointing and something we have to look at very closely."
The thrilling second half culminated in Nottingham grabbing what proved to be the decisive try from Alex Shaw after a brilliant driving maul from outside the 22.
But the outcome should not really have been in doubt as Nottingham looked certain winners, having built a solid platform during an impressive opening period.
The hosts, playing in eye-catching pink shirts as part of a special Ladies Day fund-raising effort for Breast Care Cancer, led inside a minute when some sloppy Scottish handling allowed Ayoola Erinle to boot the ball forward and dive over.
James Arlidge added the conversion - the first of his two successful kicks.
That set the tone for a one-sided opening period in which Mike Penn bundled over after a bulldozing run from Sione Kalamfoni and Charlie Hayter also crossed.
But London Scottish upped the tempo after the interval, Augustin Gosio touching down in the right corner before Guy Armitage went over to reduce the lead to two points.
James Brown gave the visitors a brief lead with one of four successful kicks but home full-back Keiran Hallett, who slotted three kicks in total, restored Nottingham's lead, and Shaw's fine team try gave them breathing space.
Delaney's men suffered a late scare when Stephen Pape went over for five points, Brown adding the extras. But, although Nottingham held on for a bonus-point win, Delaney was far from happy.
"If you look at the first half," he said, "We stuck to our processes and delivered a good set of outcomes. We missed four tackles in the whole half, didn't really look under threat and they hadn't really got near our line.
"Then the second half, we've gone off-piste with some concentration errors. These guys have to look very hard at what they are doing out there and, if the concentration errors keep costing us, we'll be looking to give others a chance."
Nottingham, who have now won four and drawn two of their nine Championship matches, lie seventh in the table.