Madrid - Friday marks 15 years since Carles Puyol made his debut for Barcelona and coach Luis Enrique might be wishing he had someone of the calibre of the shaggy-haired former defender still in his ranks.
Puyol, who retired aged 36 at the end of last season after battling a series of injuries, became a huge fan favourite at the Nou Camp with his swashbuckling captain's performances and never-say-die attitude.
As Barca prepare for a trip to Madrid to play Rayo Vallecano on Saturday, they are still reeling from Tuesday's 3-2 Champions League reverse at Paris St Germain, when their defence was badly exposed by the Ligue 1 title holders.
After Puyol announced he was ending his career, Barca brought in two centre backs to replace him, Jeremy Mathieu from Valencia and Thomas Vermaelen from Arsenal.
Mathieu's form has been erratic, while Vermaelen has only just been given the all-clear after injury and has yet to make his competitive debut.
With doubts still hanging over Javier Mascherano, a converted midfielder, and an out-of-sorts Gerard Pique, Luis Enrique is faced with a headache in central defence, his first real challenge since taking over from Gerardo Martino at the end of last term.
It was all looking so good before the PSG game as Barca had yet to concede a goal in seven outings in all competitions and they are two points clear of Valencia and Atletico Madrid at the top of La Liga.
When it came to their first genuine challenge in the latest edition of Europe's elite club competition, however, they were found wanting at the back, something that also dogged them last term when they failed to win major silverware for the first time in six years.
"We conceded two goals from set pieces and that killed the game a little," Mathieu told reporters in Paris.
"It's Barca's minor weakness and we need to correct that," added the France international. "We'll have our lift ourselves up again quickly."
While Barca suffered a reverse in the Champions League, Real Madrid and Atletico claimed morale-boosting victories before potentially tricky La Liga outings this weekend.
Real, who fought back to win 2-1 at Ludogorets, host Athletic Bilbao on Sunday, while Atletico, 1-0 winners over Juventus, play at Valencia on Saturday.
Real coach Carlo Ancelotti has been concerned at the number of goals Real have conceded at set pieces this season and they were again breached at a corner in the Ludogorets game.
"Their goal was very similar to the ones we conceded against Atletico and Real Sociedad (in La Liga)," Ancelotti told a news conference.
"We have to cover the near post more," added the Italian, in his second season in charge after succeeding Jose Mourinho.
"Today our best headers of the ball were out there to cover the near post, like (Cristiano) Ronaldo or (Gareth) Bale, but we conceded a goal again."
Real will be facing a Bilbao side who have had a shocking start to the season.
They are 16th in La Liga and were beaten 2-1 at BATE Borisov in Champions League Group H on Tuesday.