The Bees managed to claim a point from a 2-2 draw despite letting the lead slip twice at the Riverside Stadium, where Boro continued to stutter after the midweek home defeat to Norwich.
Monk said: “The intention of the players is clear, they want to go and do the right things, but, strangely, I sense a bit of anxiety in them.
“It led to certain mistakes with the ball, the goals we conceded were from our own doing. A set-piece for the first, probably the first we have conceded from a set-piece.
“Credit to them for getting back into it again and maybe they could even have nicked a winner. There has to be some perspective, though, because we have lost one in nine. Yes, we want more, yes, we want more in the performance, but we have lost one in nine.
“The last international break we talked about needing improvements and they came, this international break we need to look to correct and make further improvements. We need to come out firing like we did last time.
“Our crowd has been great, the players are fully committed, the intention is clear. I can say that honestly. We have spoken about having more confidence, of course we see that and we will work on those things during the break. That’s when we do get the chance to work hard on those.”
Brentford chief Dean Smith claimed referee Paul Tierney refused to shake his hand after he had questioned a penalty decision.
Smith felt Brentford should have had a spot-kick when Kamohelo Mokotjo appeared to be tripped in the area by Adam Clayton in the first half, only for the officials to play on.
Brentford took the lead just before the half-hour when Yoann Barbet nodded in Ollie Watkins’s delivery. Boro fought back after the restart to level through Martin Braithwaite in the 68th minute, only for Watkins to reclaim the lead four minutes later.
Boro, who have fallen behind in each of their last four matches, earned a point when full-back Fabio da Silva arrived to convert at the back post with 14 minutes left.
Middlesbrough: Randolph, Christie, Shotton, Gibson, Da Silva, Traore (Fletcher 46), Howson, Clayton, Johnson (Bamford 64), Assombalonga, Braithwaite (Baker 79). Unused substitutes: Konstantopoulos, Friend, Leadbitter, Fry.
Brentford: Bentley, Dalsgaard, Mepham, Barbet, Henry (Clarke 36), Mokotjo (Sawyers 73), Woods, Yennaris (McEachran 73), Jozefzoon, Maupay, Watkins. Unused substitutes: Archibald, Shaibu, Daniels, Sorensen.
Referee: P Tierney (Lancashire).