MIDDLESBROUGH'S promotion ambitions suffered yet another dent this afternoon as they crashed to a thumping defeat at Crystal Palace.
Boro have now lost six of their seven Championship matches in 2013, and any morale boost that might have accompanied Tuesday's home win over Leeds quickly evaporated at Selhurst Park.
Glenn Murray scored twice to take his tally for the season to 27, with Palace defender Peter Ramage and veteran striker Kevin Phillips also finding the target as the hosts ran out comprehensive winners.
Boro were second best throughout, and while Faris Haroun ensured the visitors did not finish goalless, it is hard to see Tony Mowbray's side remaining in the top six unless their performances improve markedly in the remainder of the campaign.
With Seb Hines and Jonathan Woodgate both unavailable, Mowbray was forced to name a makeshift back four that featured George Friend at centre-half and Andy Halliday at left-back.
As a result, Boro were defensively suspect from the off, and it was no real surprise when Palace claimed the lead in only the ninth minute.
Their goal was something of a horror show from a Boro point of view, with Faris Haroun making a complete hash of an attempted clearance in his own penalty area as he missed the ball completely.
Wilfried Zaha seized possession, and after surging past Halliday, the highly-rated winger crossed for Murray to score from the edge of the six-yard box.
Zaha, who has been loaned back to Palace following January's £15m move to Manchester United, caused problems all afternoon.
His pace was too much for Halliday, and he was even more effective when he was switched to the opposite flank to take on Stuart Parnaby.
His 23rd-minute cross would have led to a second goal had Murray not failed to connect with it by inches, and another centre a minute or so later resulted in Murray heading over when well positioned at the back post.
Boro were jittery throughout the first half, and when Jason Steele hurried his clearance in the 32nd minute, Stephen Dobbie almost found the target from 35 yards with the Boro goalkeeper out of his goalmouth.
Things were much less eventful at the other end, with the Teessiders struggling to gain possession before the break, but the Palace goalmouth was finally threatened in the 39th minute.
Mustapha Carayol crossed from the left, and after Haroun drilled in a low shot at the back post, former Newcastle centre-half Ramage was forced to make a sliding clearance from his own goalline.
Boro went close again in first-half stoppage-time, but after Lukas Jutkiewicz failed to connect with Haroun's low cross, Josh McEachran ballooned a shot over from 12 yards after the ball broke kindly in his direction.
The miss proved costly as the Boro defence imploded again three minutes after the interval. The problems began when Friend needlessly conceded a corner, and intensified when Stephen Dobbie delivered the set-piece into the middle.
Murray was able to head the ball back towards the goal, and despite having Andre Bikey at his back, Ramage was able to swivel unchallenged in the area before prodding the ball home.
The gulf between the sides for the majority of the second half was pronounced, and Palace added a third in the 57th minute.
Friend won a tackle in his own half, but Murray reacted quickest to pick up the loose ball, and after turning back towards goal, the in-form striker hammered home his 27th goal of the season from 25 yards.
Boro claimed a consolation with ten minutes left when Ishmael Miller back-heeled the ball into Haroun's path, enabling the midfielder to race clear and slot a low finish past Julian Speroni.
However, Palace deservedly restored their three-goal lead shortly after. Yannick Bolasie played in Phillips, and the former Sunderland striker held off Friend before drilling into the left-hand corner.
CRYSTAL PALACE (4-2-3-1): Speroni; Richards, Ramage, Delaney, Parr; Jedinak, Dikgacoi (Butterfield 76); Zaha, Dobbie, Williams (Phillips 71); Murray.
Subs (not used): Price (gk), Bolasie, Wilbraham, Moxey, O'Keefe.
MIDDLESBROUGH (4-4-2): Steele; Parnaby (Dyer 57), Bikey, Friend, Halliday; McEachran (Bailey 59), Leadbitter, R Williams, Haroun; Carayol, Jutkiewicz (Miller 59).
Subs (not used): Leutwiler (gk), McManus, Ledesma, Emnes.