Sergio Aguero and Daniel Sturridge obviously raise the level of talent of their respective Manchester City and Liverpool clubs.
The availability of both continues to be closely followed heading into Saturday's high-profile clash at the Etihad Stadium between the Premier League front-runners and the Reds as they continue to establish their identity under Jurgen Klopp.
Aguero has missed seven games across all competitions since decimating Newcastle United's defence for five goals in a 20-minute span of Manchester City's 6-1 thrashing Oct. 3. The Citizens (8-2-2), though, have gone 5-2-0 in that span while fending off Arsenal to top the table on goal differential.
It may be an ideal time for the Argentina international to return, given City went into the international break on a dour scoreless draw at Aston Villa on Nov. 8. Manchester City did not allow the hosts a shot on goal but had only three themselves as they were held off the scoresheet for only the second time in 18 matches across all competitions.
"I do hope I can play in this game," said Aguero, who leads the team with eight goals in just nine matches all season, to Manchester City's official website. "It's been a frustrating time. I'm doing everything in my power to get to the match in top condition."
The return of Aguero may let Raheem Sterling ease into his first match against his former club since his contentious departure from Anfield in the offseason in pursuit of a Champions League title. He has four goals in 11 league matches, and the 20-year-old is still trying to justify City's £49 million transfer fee as well as maintain a regular spot in Manuel Pellegrini's starting XI.
Another player who could be available if healthy is David Silva, who like Aguero has not played since the victory over Newcastle United, but still has a team-high six assists in league play.
The injuries have allowed Pellegrini to showcase his staggering and arguably unrivaled depth. Kevin De Bruyne has joined Sterling in picking up the slack of Aguero's and Silva's absences with three goals and four assists in league play, and all that quality surrounding Yaya Toure has made the Ivorian resurgent to the point where comparisons are being made to his 2013-14 form that helped City claim their second Premier League title in club history.
"We need a big squad because we've got lots of games and many competitions we're trying to win, and all the players we've brought in over the summer have made us stronger," Aguero said.
Sturridge, meanwhile, has had his silverware appetite whetted following his 22-goal 2013-14 campaign as Liverpool finished runners-up to City and the subsequent Champions League endeavour that ended with a group-play exit. Like Aguero, he has missed his team's last seven games recovering from a knee injury, which means he also has yet to play for Klopp, who replaced Brendan Rodgers following a 1-1 draw in the Merseyside derby at Everton on Oct. 4.
"He is as fit as he can be after this long break. He has trained with us," Klopp said at his Thursday news conference. "The problem with Daniel's quality is that everybody can see it - it is obvious. He is an unbelievably strong player.
"We can take him to Manchester but he has to train around the game. ... Everybody wants to see him on the pitch and we have to find the right balance. We will see - I haven't decided."
Liverpool (4-5-3) are 10th in the table on 17 points, trailing their neighbours on goal differential as they continue their transition to Klopp's "gegenpressing" style of high pressing to regain possession and forcing the opponent to move backwards. The Reds are 3-3-1 overall under the German, who has had nearly two weeks to rue his first defeat while in charge at Anfield - a 2-1 home setback to Crystal Palace on Nov. 8 in which they conceded a late winner.
While Klopp is making his first go-round in the Premier League, he has faced Manchester City before, claiming four of a possible six points with a 1-0 home win and a 1-1 road draw while in charge of Borussia Dortmund as they eventually finished runners-up to Bayern Munich in the 2013 Champions League.
Though Sturridge could feature in this match, captain Jordan Henderson has been ruled out as he continues to recover from a foot injury. Klopp is hoping to have ex-City players James Milner and Kolo Toure available for selection as well as Jordon Ibe.
Each team captured three points at home last season, with Aguero scoring following a brace by the departed Stevan Jovetic in a 3-1 victory in the corresponding fixture. Sterling provided assists on goals by Henderson and Philippe Coutinho as Liverpool countered with a 2-1 win at Anfield in the most recent meeting.