The Tannadice side sat second in the Scottish Premiership at the start of the festive week but suffered a 4-1 drubbing to St Mirren on Boxing Day, lost 3-0 to St Johnstone last Sunday before starting 2014 with another defeat after Pawlett grabbed a last-gasp winner in the Dons' 2-1 win on Tayside.
Seven of those players came back in for the meeting with the Reds but could not save United from a third defeat in a week as they slipped six points behind Aberdeen and eight behind second-placed Motherwell.
Now Pawlett claims McNamara got his team selection all wrong.
The 22-year-old said: "Dundee United rested a few players against St Johnstone and it was as though they treated this as the big game for them.
"When we saw that we thought they were giving us respect and think we're a decent team. Maybe they didn't show enough respect to St Johnstone.
"I think over the 90 minutes we looked the stronger, fitter team so maybe it was a mistake by them."