MIDDLESBROUGH were afforded no respite from their Premier League toils as the class of Pep Guardiola's Manchester City proved too much as the visitors secured a comfortable progression to the FA Cup semi-finals at the Riverside.
Goals in each half from David Silva and Sergio Aguero saw City book a Wembley berth and Boro could have no complaints with the gulf in class firmly evident in a one-sided second-half with the Lancastrians threatening to ran riot with keeper Brad Guzan making several fine saves.
Boro showed spirit in the opening period after going behind early on to Silva's third-minute strike, but the Teessiders were given a complete chasing in the second period as City moved through the gears in exhibition fashion at times.
After spurning several chances to grab a decisive second goal, it finally arrived on 67 minutes when Aguero coolly converted Leroy Sane's low cross for his 24th goal of the season.
It ultimately proved another tough afternoon for Boro, who also lost Rudy Gestede and Bernardo to injuries to compound matters for beleaguered manager Aitor Karanka.
City fielded a strong line-up with Silva, Raheem Sterling, John Stones and Pablo Zabaleta being among those recalled - and it took their star-studded line-up just a few minutes to make the breakthrough.
Boro had barely touched the ball with a neat move ending with Yaya Toure finding an unmarked Zabaleta down the right - with his dangerous cross fired home from close range from Silva after Sterling initially failed to make contact.
It was the worst possible start for beleaguered Boro and the early signs looked ominous for the disjointed hosts.
Leroy Sane sped away from Antonio Barragan on 15 minutes following Kevin De Bruyne's slick pass, but his cross-shot was tame with the Teessiders afforded a let-off.
Boro's best hope looked the set-piece route and it went desperately close to yielding a 22nd-minute leveller - and palpably gained encouragement from that as City started to lose their way a little bit.
Rudy Gestede climbed well following Grant Leadbitter's corner and his point-blank header was unconvincingly spilled by Claudio Bravo before rebounding off Zabaleta and being hacked clear by Toure - to provide some overdue encouragement for Boro.
But the hosts were afforded a blow soon after with Gestede limping off with what appeared to be a hamstring injury, with ex-Blues striker Alvaro Negredo coming on.
After a low-key spell, City rediscovered their poise with Sane missing a golden chance to double their advantage from close in, scuffing his shot after latching onto Sterling's cut-back with Boro undressed down their left.
Soon after, Sane left Barragan and Bernardo for dead, but couldn't pick out a team-mate following a sublime run.
A inviting Marten De Roon cross then picked out Cristhian Stuani, whose firm header was held by Bravo before Brad Guzan gathered Silva's low shot at the other end.
The last chance of the half fell to City with De Bruyne's free-kick finding Toure, whose header flew wide.
City turned up the heat early in the second half and went mighty close on three occasions in quick succession to sealing their progress in a powerhouse spell of pressure.
First, Silva, untypically, showed a lack of composure to blaze an excellent chance over following good work by the classy De Bruyne before Sterling supplied Aguero, whose low point-blank strike was somehow diverted by the feet of Guzan onto the post.
Zabaleta then fired wide under pressure from Grant Leadbitter as the visitors went for the throat.
Next to threaten was Sane, who ghosted in down the left before a timely intervention from Ben Gibson blocked his goalbound shot, with Boro making little headway at the other end.
Still, the killer second wouldn't come for City with the increasingly busy Guzan making fine one-handed saves to keep out efforts from distance by Silva and then Sane.
The second goal that City merited finally arrived on from a familiar source.
The impressive Sane got away down the left and his low cross was clinically dispatched by the lurking Aguero.
The increasingly dominant Silva almost added a third minutes later as City threatened almost at will.
Boro's first serious incursion of the half almost brought a consolation goal with Fabio's header cleared off the line by Nicolas Otamendi.
But the half fully belonged to City, who ran rings around the hosts in an outstanding second half.
Guzan made another smart save to deny Sterling as the game went into the final ten minutes.
Middlesbrough: Guzan; Barragan, Bernardo (Fry 50), Gibson, Fabio; Clayton, Leadbitter (Ramirez 66); De Roon, Stuani, Traore; Gestede (Negredo 26). Unused substitutes: Valdes, Fischer, Forshaw, Husband.
Manchester City: Bravo; Clichy, Otamendi, Stones, Zabaleta; Yaya Toure (Fernando 86); Sane (Nolito 69), Silva, De Bruyne, Sterling; Aguero (Iheanacho 90). Unused substitutes: Caballero, Kolarov, Delph, Fernandinho.
Referee: M Dean (Wirral).