The outcome of Chelsea's Champions League round-of-16 clash with Barcelona will not have a decisive impact on head coach Antonio Conte's uncertain position, according to Deco.
Chelsea have mounted a disappointing defence of their Premier League title and sit fourth in the table, 19 points behind runaway leaders Manchester City.
They face a demanding European encounter with LaLiga frontrunners Barca at Stamford Bridge on Tuesday, followed by meetings with Manchester United, City and Crystal Palace in the league before the return fixture at Camp Nou next month.
Conte has been widely tipped to depart the Blues at the end of the campaign after just two seasons in charge.
Nevertheless, former Portugal international Deco, who starred for both Barca and Chelsea during his playing career, does not expect club owner Roman Abramovich to dispense with the coach based on the two legs of the Barca showdown.
"I'm not in the daily routine of Chelsea, Chelsea nowadays is a big club and all big clubs have the pressure of [needing] victories, even being in England, where managers tend to stay longer," he told Omnisport.
"But Chelsea's history is not the same of other English teams, of course this will be a challenge. To be defeated by Barcelona won't be a disaster. Of course, Chelsea wants to get through, but I don't think their manager's work will be evaluated by this. That's a problem [for] them and they know what to do."
Deco feels the departure of two key players in the off-season has exerted a negative impact on the team's fortunes, as they battle to finish in the top four and retain their berth in UEFA's elite club competition.
"To lose Diego Costa and [Nemanja] Matic, they were two important players to Chelsea, even though [Alvaro] Morata had a very good beginning, he's not a substitute for Diego yet," he said.
"The way Chelsea played... [they haven't] found yet the same football they had last year.
"But problems are normal, when you don't win and don't achieve the goals of such a big club like Chelsea, it's always difficult."
|Liverpool ´made a point´ with PSG victory - Gomez|
|Osaka wows Tokyo crowd on WTA return|
|Excited Povetkin arrives in England for Joshua showdown|
|Kovac patience with Sanches set to reap rewards|
|Kovac: Madrid strong without Ronaldo, Messi is the best|
|ATP suspends umpire Lahyani over Kyrgios ´pep talk´ at US Open|
|North and South Korea seek to co-host 2032 Olympics|
|Ampadu signs long-term Chelsea contract|
|Don´t blame Neymar, PSG players all guilty - Thiago Silva|
|Real Madrid seek to plug Ronaldo scoring gap – Champions League in Opta numbers|
|Brewers allow Cardinals to inch closer with loss to Reds|
|Manchester is still red – Depay ahead of Lyon´s clash with City|
|Orioles become first pro team to wear braille jerseys|
|Klopp hails ´brilliant´ Henderson|
|PSG attack lacked aggression, says Tuchel|
|Atletico Tucuman 0 Gremio 2: Libertadores holders draw first blood in QFs|
|Thomas plays down wrist worry|
|Rakitic wants more from Barcelona hat-trick hero Messi|
|My players aren´t s*** – Pochettino defends Spurs squad|
|Cubs reliever Morrow won´t return this season|
|Tebow expected to be back in Mets organisation next season|
|Inter can compete against anyone – Icardi revels in Champions League victory|
|Tuchel: PSG loss to Liverpool not logical or correct|
|Sturridge in best shape I´ve seen – Klopp|
|Milojevic celebrates ´fantastic´ occasion after Red Star´s 26-year wait|
|Rodrigo and Simeone salute Griezmann display|
|Seahawks DE Clark on Bears QB Trubisky: He´s nothing special|
|Carroll says Wilson has been ´over-trying a little bit´|
|Judge returns to Yankees´ starting lineup|
|Napoli boss Ancelotti takes aim at Red Star time wasting|
|Favre admits young Dortmund stars struggled in Bruges|
|Otavio would trade goal for Porto victory as he bemoans Schalke draw|
|Championship Review: Pacesetters Leeds crush Preston, Villa end five-game winless run|
|Neymar world-class but not a defender - Klopp says Liverpool targeted PSG star|
|Waiters injury update: Heat guard unlikely to be ready for start of season|
|Gojowczyk eliminates returning Tsonga in Metz|
|Liverpool enjoying best start in 57 years after PSG win|
|Galatasaray 3 Lokomotiv Moscow 0: Terim´s side make light work of Russians|
|Club Brugge 0 Borussia Dortmund 1: Super sub Pulisic scores late winner|
|Schalke 1 Porto 1: Fahrmann saves one penalty, but Otavio scores another|
|Red Star Belgrade 0 Napoli 0: Points shared as Italians fail to make possession pay|
|Liverpool 3 Paris Saint-Germain 2: Firmino strikes late as Reds edge five-goal thriller|
|Monaco 1 Atletico Madrid 2: Costa and Gimenez seal comfortable win|
|Chaos reigns in Serie B as league denies suspension claim|
|India secure Asia Cup victory despite valiant Hong Kong effort|
|Messi makes "extraordinary routine", says Valverde after Barca star surpasses Ronaldo|
|Spalletti´s Inter to take heart from Tottenham turnaround|
|Casillas features in landmark 20th Champions League campaign|
|Spurs deserved more from best performance of the season - Pochettino|
|Brown absent from Steelers facility on Monday due to ´personal matter´|
|Toronto´s Bussey given eight-match biting ban|
|Barcelona 4 PSV 0: Marvellous Messi lights up Camp Nou|
|Inter 2 Tottenham 1: Icardi, Vecino complete dramatic late turnaround|
|Allegri, Chiellini defend Costa over spitting ban|
|Firmino only fit enough for bench duty|
|Kovac applauds Sanches ahead of Benfica homecoming|
|Tomlin confirms Steelers WR Brown was absent from facility on Monday|
|Mourinho tells United to follow Federer´s lead amid Young Boys pitch concerns|
|Costa banned for four Serie A matches for spitting|
|PGA Tour announces changes to FedEx Cup Playoffs format|
|Rashford to start against Young Boys, Mourinho confirms|
|Ryder Cup heading to Congressional in 2036|
|I never listen to stupid things - De Gea unconcerned by criticism|
|Aguero trains as Mendy sits out Man City session|
|Lampard fined after accepting improper conduct charge|
|Serie B suspended after Pro Vercelli win appeal|
|Mitchell returns to England as defence coach|
|Brady completes Cornet upset in Guangzhou|
|Lopetegui giving no guarantees to ´fighter´ Navas|
|Di Francesco denies racially abusing Costa|