TWO-GOAL Marc-Antoine Fortune steered Albion to their first victory of the season - and a comfortable passage into the Carling Cup third round.
The Baggies just about deserved their two-goal half-time cushion thanks to fit-again Jerome Thomas' neatly-taken eighth-minute goal and Fortune's first of the night three minutes before the break.
League One Bournemouth rallied briefly when Steve Lovell reduced the arrears two minutes after the re-start.
But the impressive Simon Cox restored Albion's two-goal cushion on 53 before strike partner Fortune put Roy Hodgson's dominant side 4-1 up with a superb individual effort 12 minutes from time.
Hodgson's decision to ring 11 changes from the luckless defeat at Chelsea, and make full utilisation of his squad, fully paid off at the Seward Stadium - much to the delight of the impressive 789-strong travelling support.
And it was an encouraging night for the club's youth system, with no less than six Academy graduates named in the 18-man squad.
Summer signings Gareth McAuley, Billy Jones and Marton Fulop, plus young defender Craig Dawson, all made their first competitive appearances for the club while 18-year-old midfielder George Thorne was granted his full debut.
The team, which included a fit-again Thomas (groin), was skippered by Graham Dorrans while Bournemouth included on-loan Wolves defender Scott Malone in their XI. Ex-Baggies loan signing Warren Cummings was among their subs.
With so many changes, it was hardly surprising that Albion took a while to settle into their stride.
But they broke the deadlock on the south coast with their first attack.
In the eighth minute, Dorrans spearheaded a slick passing move which resulted in Marek Cech slipping in Thomas inside the left-hand side of the box and the winger composed himself before curling a crafty right-footed effort inside the far post from the tightest of angles.
Thomas was at it again just four minutes later when he collected Cox's lay-off and beat two defenders before losing his footing at the vital moment and shooting well wide from 15 yards.
In what was proving a very open second-round tie, Bournemouth had already peppered the Baggies box with a barrage of crosses when Malone saw a speculative 25-yard volley arc well wide of the far post.
Thorne, who committed himself to the club until 2015 earlier today after being rewarded with his second new contract of the summer, was at the heart of all of Albion's good work as they prodded and probed for a second goal.
But the Cherries were exerting plenty of pressure down the Albion left and, on 24, Lyle Taylor flashed a free 15-yard header well over from Liam Feeney's centre.
Albion broke straight up-field and after Thomas won a free-kick in a central position 25 yards out, Dorrans saw his ferocious right-footed drive pushed out by Bournemouth keeper Daryl Flahavan. Fortune pounced on the rebound and was unlucky to have his goalbound effort blocked by a Cherries defender inside the six-yard box.
Thomas was enjoying a lively game and another jinking run into the box from the left resulted in the former Arsenal man seeing a right-footed drive deflected wide for a corner.
But Albion were almost caught out in the 41st minute - and they would only have had themselves to blame.
While they were protesting the awarding of a free-kick against Cox, the Cherries quickly took the set-piece and Feeney saw his terrific right-wing centre headed wide by Adam Barrett from eight yards.
But Albion made the most of their reprieve by surging two-up three minutes before half-time.
The workmanlike Cox dispossessed Harry Arter along the right-hand by-line and pulled the ball back to Fortune, who slid home from eight yards.
Thomas' work was done at half-time as Hodgson replaced him with Joe Mattock.
Albion had finished the first half in comfortable fashion - but the tie was very much alive again within two minutes of the restart.
Patient build-up play led to Malone racing clear down the left and his low cross was slid home by Lovell.
However, Bournemouth's joy was short-lived as the Baggies restored their two-goal cushion just six minutes later.
Jones was very much the architect, powering forward on a 60-yard run before slipping in Cox, who coolly side-footed past Flahavan from 15 yards.
Albion came within a whisker of making it 4-1 just past the hour-mark when the advanced Mattock smashed a left-footed drive off Flahavan's near post from 25 yards.
The Baggies were firmly in control and Flahavan had to race out of his box to prevent Cox getting on the end of Dorrans' through-ball after the visitors had swiftly turned defence into attack.
Dorrans was producing a dominant performance in central midfield and went close when his right-footed free-kick clipped the Cherries wall and looped just wide.
The Scotland international took the ensuing corner and Cox almost grabbed himself a second when he did brilliantly to control a loose ball inside the penalty area, only for his audacious overhead kick to screw wide.
The tie was done and dusted 12 minutes from time.
Fortune controlled Cech's cross with his back to goal before spinning Shaun Cooper and blasting home a fine individual goal.
Albion had chances to add a fifth during the dying stages, with Dorrans having a 25-yard free-kick pushed away by Flahavan before Cox failed to posh off a terrific flowing move involving sub Roman Bednar, Cech and Dorrans by stabbing wide from 12 yards.
BOURNEMOUTH (4-4-2): Flahavan; Byrne, Barrett (c), Cooper, Malone; Feeney, Molesley (Baudry 62), Arter, Pugh; Taylor (Stockley 75), Lovell (Purches 89). Subs not used: Jalal (gk), Fletcher, Cummings, Ward.
ALBION (4-4-2): Fulop; Jones, McAuley, Dawson, Cech; Jara Reyes, Thorne (Mantom 82), Dorrans (c), Thomas (Mattock HT); Cox, Fortune (Bednar 79). Subs not used: Daniels (gk), Downing, Hurst, Roofe.
GOALS: BOURNEMOUTH - Lovell (47). ALBION - Thomas (8), Fortune (42 & 78), Cox (53).
BOOKINGS: BOURNEMOUTH - Lovell (foul 49).
REFEREE: R East (Wiltshire).
ATTENDANCE: 6,911 (789 Albion fans).
ALBION STARMAN: Graham Dorrans.