Rafael Benitez is tomorrow expected to become the first manager to make the momentous decision to drop both Frank Lampard and John Terry from a Chelsea team to start a major cup semi-final or final.
Chelsea have played in 34 semi-finals or finals since Roman Abramovich became owner in 2003 and, during that period, both Terry and Lampard have never missed a game for which they were fully fit and available.
Benitez has been rotating his squad over recent weeks and, ahead of the biggest game of the club's season, he appears to be preparing to gamble on a decisive departure from the most successful era in Chelsea's history.
Asked specifically about the difficult of leaving out 'big-name' players, Benitez said: "To leave any player out of the team, especially when they are training and working hard, is quite difficult. But it's something you have to do. And you have to explain to them. It depends on the players.
"Some are only okay if they go and will play. Some can't play at the same level two games in a row. You have to make decisions."
Lampard played the entire 90 minutes of the Europa League second leg against Rubin Kazan on Thursday and it appeared significant that Ramires was the midfielder replaced by John-Obi Mikel once the game was secure. The expectation tomorrow is that Ramires and Mikel will play in holding positions in front of the defence, with Oscar, Juan Mata and Eden Hazard starting further forward.
Lampard admitted that he did not know whether he would start, and it was put to him that he had previously always been an automatic selection.
"That depends on how you're playing and what manager you have, and relationships, and things change," Lampard said. "I don't think anyone is an automatic selection with the manager at the minute as we see because there are lots of games and he's changing it regularly.
"We're not sure we're playing on Sunday. I'm like everyone else: I want to play every game but it's not possible."
Lampard and Terry have started every FA Cup semi-final and final since 2006, playing every minute as Chelsea won seven times at Wembley on the way to lifting the trophy in 2007, 2009, 2010 and 2012.
The sense of changing times will be further underlined tomorrow by the unavailability through injury of Ashley Cole and the absence on such a big occasion of the departed Didier Drogba.
"I don't think our record gives us an advantage, particularly in a game against City's quality," Lampard said. "If they're at their best and we're not, they'll probably win the game and vice versa."
Terry also started in Moscow on Thursday and Benitez is expected to rotate his squad tomorrow by recalling Branislav Ivanovic in central defence alongside David Luiz. Ryan Bertrand should also return at left-back, while Demba Ba is likely to replace Fernando Torres as the main central striker.
Benitez has consistently explained his selection decisions with reference to the fixture schedule and qualification for the Europa League semi-final means that Chelsea are facing as many as 12 matches in the final five weeks of the season.
The Spaniard believes that this schedule – his team have also played five times in the past fortnight – will give Manchester City an advantage tomorrow.
"It's always an advantage," he said. "I have too many games and we have to use the squad. The players are doing really well.
"I think I have done a good job. If we finish in the top three and win one of the trophies or both, I will be really pleased and really proud."
City are expected to leave out one of their own star names, with Joe Hart's FA Cup absence likely to continue, with Roberto Mancini predicted to extend Costel Pantilimon's run of appearances in the competition.
England goalkeeper Hart has not played in the FA Cup for City since helping the club end their 35-year trophy drought by defeating Stoke City in the 2011 final.
And despite the significance of the match with the holders tomorrow, the City manager is understood to be leaning towards Pantilimon in goal.
Romania international Pantilimon, who arrived from FC Timisoara for an undisclosed fee in the summer of 2011, has yet to concede a goal in the FA Cup this season after playing in all of City's ties.
Although Hart has endured a difficult season, Mancini has remained loyal to the 25-year-old in the Premier League and Champions League and his omission against Chelsea would be regarded as usual selection policy for domestic cup matches rather than the club's first choice being dropped.
Mancini, meanwhile, insists he is not under greater pressure to guide his team to the cup final with the Premier League title seemingly now out of reach, despite City's 2-1 victory at Manchester United on Monday.
"The semi-final is important for me, for the players and for the club because it is another semi-final and we have the chance to reach another final and to win another trophy," Mancini said.
"For these reasons it is important. It is very important to continue to win trophies.
"I don't think it will be easy because it will be a difficult game. But it will only be the same pressure that any team would have playing in a semi-final."
David Silva will have a fitness test on a hamstring injury tomorrow morning to assess whether he is fit to play, but Sergio Aguero could return after being forced to start the United game as a substitute because of a knee problem. (© Daily Telegraph, London)
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