Gerard Pique rescued Barcelona a point against Espanyol as a bad-tempered Catalan derby, marred by heavy rain, ended 1-1 on Sunday.
Pique's late header atoned for his error in losing Gerard Moreno for Espanyol's opener, but a wash-out made conditions for a spectacle impossible, while seven yellow cards were dished out.
Ernesto Valverde rested Lionel Messi for the trip to Cornella-El Prat as Paco Alcacer and Coutinho flanked Luis Suarez and were joined by new faces Lucas Digne, Nelson Semedo and Paulinho.
Espanyol beat Barca 1-0 in their Copa del Rey quarter-final first leg on January 17, but the Blaugrana overturned the deficit a week later to reach the last four, making this their third meeting in the space of little over a fortnight.
Much like the two cup ties, not much quality was on show as Espanyol were determined to get under the League leaders' skins and make life as uncomfortable for them as possible.
The torrential conditions also played their part in stifling the visitors' rhythm, although only the bar stopped Philippe Coutinho's curler from flying past Pau Lopez against his former club.
Sergi Roberto and Messi were thrown on early in the second half, but not even the No 10 was able to click the visitors into gear, and when Pique mistimed his clearance from a Leo Baptistao cross, Gerard was there to nod it home.
However, the defender lived up to his promise of "making headlines" for the Spanish Press in the final 10 minutes, towering a header past Pau from a corner.
Some late handbags also saw the two goalscorers square up, but Barca nonetheless moved 12 points clear at the top of La Liga and 19 of fourth-placed Real Madrid.
Espanyol 1-1 Barcelona
Moreno 66 (E) Pique 82 (B)
Espanyol: Pau; Marc Navarro (Javi Lopez 76), Naldo, David Lopez, Aaron; Jurado, Granero, Darder, Victor Sanchez; Jurado (Sergio Garcia 61); Gerard, Baptistao (Carlos Sanchez 86)
Barcelona: Ter Stegen; Semedo (Sergi Roberto 59), Pique, Umtiti, Digne (Alba 75); Paulinho, Busquets, Iniesta; Alcacer (Messi 59), Suarez, Coutinho
Referee: Gil Manzano