Liverpool suffer blow as Coutinho is ruled out with shoulder injury until end of October. (Reuters)

Liverpool's bright start to the new Premier League season has been struck a blow after the club confirmed Coutinho will be ruled out until the end of October with a shoulder injury.

The Brazilian midfielder suffered the knock during his side's 2-2 draw with Swansea after a robust challenge from Ashley Williams forced Brendan Rodgers into substituting the 21-year-old.

The Reds boss confirmed earlier this week Coutinho would undergo a scan to assess the injury and it has been decided that the former Inter starlet will need surgery on the AC joint in his shoulder, possibly ruling him out of his side's next six games.

Coutinho has been one of the club's most influential players since his arrival from Inter last January, swiftly becoming accustomed to life in the Premier League and making the no. 10 position behind either Daniel Sturridge or Luis Suarez his own.

Brendan Rodgers admitted after his side's draw at the Liberty Stadium that his side lacked that incisive edge when the Brazilian was taken off with his injury. Coutinho was replaced by Iago Aspas after 55 minutes and just 10 minutes later Swansea found an equaliser through Jonjo Shelvey.

"I thought the assessment was simple. In the first 65 minutes, we were very good, both with and without the ball, and we looked really in control for that first 25 minutes," Rodgers said following the draw against his former club.

"We showed great character to come from behind so early on in the game, but probably young Coutinho going off disrupted the flow of our game."

During his surgery and subsequent recovery period, Coutinho will miss home games against Southampton, Crystal Palace and West Brom and away trips to Sunderland, Newcastle and the Capital One Cup clash with Manchester United.

Without the influence of the 21-year-old, Rodgers does have options in efforts to make up for his absence.

Luis Suarez is eligible to return for the Reds next Wednesday in the club's cup match at Old Trafford, and the Liverpool boss could elect to partner the Uruguayan up front with Sturridge rather than opt to play one of them in the hole or out wide.

Alternatively, Rodgers may consider the option of Luis Alberto. The versatile 20-year-old, signed from Sevilla during the summer, can operate in a number of attacking positions and strengthened his claim for a first team role with an impressive hat trick for the U21 side in their U21 Premier League win over Sunderland on Tuesday night.