Albion were unable to complete a spirited second-half comeback at The Hawthorns as their Emirates FA Cup progress was halted by Premier League Newcastle United.
Goals from Matt Phillips and Ken Zohore ensured a tense finish at Albion HQ after the Magpies earned what appeared to be an unsurmountable three-goal lead.
Slaven Bilić made four changes to the side that recorded a fourth-round victory at West Ham United in January with Kieran Gibbs returning from a hamstring injury.
Kyle Edwards almost fired Albion into a fourth-minute lead but was frustrated by Karl Darlow who parried the winger’s fierce right-foot strike from 20 yards.
Baggies stopper Jonathan Bond, who recorded clean sheets in each of the previous two rounds, was forced into action on 19 minutes, getting down low to deny Joelinton at the near post.
The visitors went close again on 29 when Allan Saint-Maximin shook the left upright with a venomous 35-yard effort.
The two sides continued to exchange blows and Charlie Austin tested Darlow once more two minutes later, but the Magpies keeper was again able to push wide from the striker’s thunderous 20-yard shot, before Kyle Bartley headed over from the resulting Chris Brunt corner.
Newcastle soon took the lead, Miguel Almiron firing past Bond and inside the right post from Saint-Maximin’s throughball.
Almiron doubled the Magpies’ advantage in first-half stoppage time, blasting home a powerful left-foot effort from 12 yards after Albion failed to defend a low ball in from the right.
United had a third just two minutes after the restart. Bond could only parry from Saint-Maximin’s low left-wing cross and Lazaro bundled in from close range.
Matt Phillips so nearly pulled one back but saw his 51st-minute lob heroically cleared under the crossbar by Danny Rose.
Filip Krovinović’s introduction just shy of the hour-mark gave the Baggies fresh impetus, but the on-loan playmaker’s low centre somehow evaded Phillips inside the six-yard box.
The Croatian was at it again moments later, firing a dipping 25-yard effort just over the bar with Darlow beaten.
Kyle Edwards went closer still on 73 when his swerving long-range effort crashed against the crossbar.
The Baggies finally got their goal seconds later with Phillips directing a controlled volley under the bar from Zohore’s smart knockdown.
Albion refused to take this one lying down and, with the visitors largely penned in their own half, they certainly had their chances.
Krovinović again forced a save from Darlow with a fine long-distance strike, before Kenneth Zohore saw his goal-bound effort cleared from the line.
Zohore made the final seconds even more interesting when he tapped in from Edwards’ low cross but the Baggies simply ran out of time with referee Anthony Taylor blowing up moments later.
Albion: Bond; Furlong, O’Shea, Bartley, Gibbs; Barry (Krovinović 57), Brunt (Tulloch 85); Phillips, Harper, Edwards; Austin (Zohore 67).
Substitutes: Al-Habsi; Townsend, Peltier, Fitzwater.