Messi opened the scoring at Camp Nou when he received a pass from Ivan Rakitic in what appeared to be an offside position.
After Espanyol forward Pablo Piatti hit the post, Messi made it a treble with a left-footed strike to slot in another pass from Alba.
"That's why I played for the national team".
A mix-up between Ter Stegen and Alba nearly gave Espanyol a lifeline in the 51st minute but Piatti's lofted shot bounced just wide.
Dembele has the unenviable task of replacing the departed Neymar and Barca's 105 million-euro man had to wait until 22 minutes from time for his debut as he replaced Gerard Deulofeu to a standing ovation.
The points were safe midway through the half when Messi and Suarez played one-twos into the box and the ball broke to Alba, with the mercurial Argentinian on hand to convert the cutback once more.
Dembele went on moments later to a round of applause from his new supporters.
Messi is now the all-time top scorer in the Catalonian derby with 17 goals.
At the Santiago Bernabeu, a much-changed Madrid paid a heavy price for a slow start as they dropped points at home for the second consecutive game.
But Barca did more than enough to sweep aside the spirited Budgerigars and now find themselves top of La Liga as one of only two sides who still hold their 100% winning record.
So fond are Espanyol of their former striker that he has a gate named after him at their stadium but on Saturday they will be hoping to take advantage of institutional instability at Barcelona to end their torrid run at the Nou Camp.
The US condemns a "variety" of attacks - "attacks on security forces, attacks on civilians (and) attacks by civilians", he said. Asked if Canada would welcome asylum claims from Rohingya Muslims, the prime minister reiterated a familiar welcoming message.
But still Ayman Hakeen's team, ranked 80th in the world and who gave never played in a World Cup, have managed to beat the odds. Australia's World Cup qualifying path could include a home-and-away match against Syria if an automatic berth is not achieved.
Speaking alongside relevant cabinet officials, Trump is expected to hold North Dakota's economy up as an example for America. State officials, in addition to North Dakota's Congressional delegation, will attend the speech in Mandan, North Dakota.
The study was led by Swiss astronomer Vincent Bourrier from the Geneva Observatory in Switzerland and colleagues. This artist's rendition shows what the surface of a planet in the TRAPPIST-1 system might look like.
The average price of premium gasoline is now $2.93 a gallon, up almost three cents over the same period. The news immediately sent US gasoline prices to a two-year high, Reuters reported Wednesday night.
There have been several previous reports of Baghdadi's death. "My personal view is I wouldn't want to repeat that", Townsend said. Baghdadi was believed to be in Mosul, Iraq, before a US-led coalition began an effort to reclaim the city in October 2016.
Lemonade pop icon Beyoncé said she was working with her charity to assist the storm and flood victims in her hometown of Houston . United Way, which is supported by almost 3 million volunteers worldwide, is uniquely positioned to respond to Harvey .
He got to San Juan on Sunday for a vacation and tried to fly back early to avoid the storm, but everything was sold out. Winds were 28 to 36 miles per hour when the flight landed, which is well below the safety limits for the aircraft.
Los Angeles resident Tracy Goldman had her vehicle packed in case officials ordered her street to evacuate. The fire crested into Burbank's hills as of late afternoon, according to the Burbank Police Department.
It is the first time in Rakhine s bitter and bloody crisis that Hindus have fled - a sign violence is billowing out. Large numbers of refugees are now stranded near the border after Bangladesh blocked their entry.
Raiders put Sebastian Janikowski on injured reserve
Giorgio Tavecchio has been promoted from the team's practice squad and will be the team's kicker until further notice. In 2011, his 63-yard field goal at Denver tied the record for longest in league history at the time.
Nadal overwhelms del Potro; faces Anderson in US Open final
Rafael Nadal claimed a hard-fought victory over Juan Martin del Potro and was a step away from his third title at the US Open . I knew it was going to be a tough one. "Maybe at the beginning he did a lot of mistakes, but I played aggressive, too".
North Korea vows strong countermeasures against USA pressure
Outside experts have been unable to verify North Korea's claim that it tested a hydrogen bomb Sunday, but say it's plausible. A fire department official in Seongju said 38 people, including six police officers, were injured, none seriously.
NFLPA files request to block Elliott suspension
The new petition is asking the US District Court in Texas to vacate the suspension if it's upheld by Henderson. Roberts testified in Elliott's appeal hearing that she did indeed recommend that he should not be disciplined.
Palo Alto again narrows loss, ups revenues in record Q4
They presently have a $155.00 price target on the network technology company's stock, up from their prior price target of $146.00. Finally, Endurance Wealth Management Inc. increased its position in shares of Palo Alto Networks by 33.5% in the first quarter.
Destiny 2 Wheels Out the Live Action Trailer to Drum Up Hype
Vogt-Roberts also talked a bit about how the whole thing came about and the creative process that went into making this trailer. So begins the live action trailer which Bungie just released to promote the September 6 release of Destiny 2 on console.