Philippe Coutinho and Steven Gerrard are back in tandem, nine years after they first began to forge an alliance at Liverpool.

Gerrard referred to Coutinho as a friend this week, but he is also set to be his boss at Aston Villa after the Brazilian agreed to join from Barcelona.

The theory is that if anyone can get a tune out of Coutinho, it should be his former Liverpool captain, given the strong relationship they had on the pitch, which has endured in the years since.

Barcelona hoped Coutinho would be a leader in their orchestra, but instead his displays often struck a bum note, and the Blaugrana are happy to have offloaded one of the most expensive signings in their history.

Exactly how much they have ended up paying Liverpool for Coutinho is unclear, given the various clauses that were in the January 2018 deal, but he cost the Catalans giants well over £100million, and the return on that investment was far from what was expected.

In LaLiga, he played 76 times, starting 51 games, and managed 17 goals and nine assists. Overall, he had 26 goals and 13 assists in 106 games.

Gerrard will be hoping the 29-year-old Coutinho can sprinkle some magic at Villa, having already shown his qualities in the Premier League.

After a slow start at Liverpool, his performances came on leaps and bounds; across his final two and a half seasons with the Reds, Coutinho managed 38 goals and 24 assists in 99 matches.

In this World Cup year, Coutinho will want to be playing regularly. Such a prospect was off the table at Barcelona, where planning for the long-term future is the order of the day, along with hacking down the wage bill.

Coutinho made an encouraging start at Barcelona, and across all competitions he managed 10 goals and six assists in just 22 games across his first half-season with the Blaugrana.

In 2018-19, he played 54 times and finished with 11 goals and five assists, with his productivity already in decline. From an average of 0.97 goal involvements (goals and assists) per 90 minutes in that honeymoon period after first arriving from Liverpool, his contribution shrank to 0.43 involvements per 90 in his first full season.

In an all-conquering Bayern side, that bounced back up to 0.84 goal involvements per 90 minutes in the 2019-20 campaign, but Coutinho could not crack on at that pace once back at Camp Nou.

Last term, as he made just fitful contributions, his involvements averaged out at 0.57 per 90, and this season's rate was just 0.3 as his inevitable exit approached.

In his final half-season at Anfield, the former Inter winger was contributing 1.2 goal involvements per game as his Reds form peaked.

Across his Reds career, Coutinho scored 19 Premier League goals from outside the penalty area, Opta said. Only Gerrard has scored more for the club from outside the box (33).

Since returning to Barcelona from Bayern, Barcelona have tended to do better when Coutinho has played no part in games.

When he has been involved, either as a starter or substitute, they have won just nine of 24 LaLiga games for a 37.5 per cent success rate, averaging 1.4 points and 1.5 goals.

But without him they have won 23 of 33 (69.7 per cent) in LaLiga, losing only three times, averaging 2.3 points and 2.4 goals per game.

It is little wonder he has played just 26 per cent of minutes across all competitions for Barcelona this season. Injuries have blighted his Barcelona career, and if this is the end, with a loan potentially leading to a sale, then all parties will be happy to move on.

Villa are signing a special player, one that Gerrard still likes to tag as a "magician", but also a footballer who perhaps needs a reminder of those old tricks in his repertoire.

If Gerrard can bring back that spark, that trickery with end results, Villa will be all the better for it.