LONDON (AP) -- All 20 English Premier League clubs enter the FA Cup this weekend after a grueling festive schedule, giving many exhausted players a chance to take a breather.
Chelsea begins its cup defense at Southampton on Saturday, with Rafa Benitez's side reeling from a four-game winning run being ended by Queens Park Rangers on Wednesday to remain fourth in the Premier League.
Striker Fernando Torres, who has started all 20 league matches this season, could make way for Demba Ba if the Senegal international completes his move from Newcastle.
"Fernando is one of the players who needs to rest. Two or three players have been playing too many games in the last weeks and months," Chelsea manager Benitez said. "Managing that was going well but against QPR it didn't work. Some of the players couldn't get to the level we were expecting.
"Without talking about names, if you have another striker you can play with two strikers if you need to. Or if you want to rest a striker then you can do that and at the moment we are a bit short."
In another meeting of topflight clubs in the third round on Saturday, Manchester United faces West Ham in a position of strength after establishing a seven-point lead in the title race over Christmas and New Year.
But despite not winning the FA Cup since 2004, manager Alex Ferguson's priority is the league and Champions League.
That means the 39-year-old Ryan Giggs and the 38-year-old Paul Scholes could be among the players to be rested for the trip to Upton Park.
"We have a big squad and you're not going to play every game," Giggs said. "The likes of me and Scholesy probably play fewer matches than a lot of the players but we know we have to be ready when we're called upon."
The cup, though, is a welcome distraction for teams like Newcastle, which is hovering above the Premier League relegation zone.
But the northeast club has a potentially tricky trip to the south coast on Saturday to face Brighton, having lost to the second-tier side in the fourth round last year.
"The FA Cup is a significant trophy and probably our best opportunity of winning something," Newcastle manager Alan Pardew said. "The Premier League comes first for us, but the FA Cup comes very much second in front of the Europa League and the League Cup."
Manchester City, which is second in the Premier League and won the FA Cup in 2011, also faces League Championship opposition when it hosts Watford on Saturday.
Liverpool will be hoping to avoid embarrassment when it plays away at nonleague side Mansfield, which plays in the fifth tier.
"The whole town is up for it," Mansfield manager Paul Cox said. "We want to give a good account of ourselves and make the supporters proud of our players. It's a fabulous time at the football club."
The lowest-ranked team remaining in the cup is seventh-tier side Hastings, which hosts Middlesbrough of the League Championship on Saturday having previously reached the first round only once.
Hastings is more famous for the battle in 1066 when the Normans under William the Conqueror defeated the English.
"This is a big deal for us," Hastings player-manager Sean Ray said. "It's our first-ever appearance in the third round so we've had a lot of people wanting to talk to us. It's been nice, but it's also been pretty hectic.
"But the players have been fantastic. I've had no trouble with anyone. They've all stayed pretty grounded."
Among Saturday's other matchups, Tottenham hosts Coventry in a rematch of the 1987 final which the visitors won, Aston Villa faces Ipswich, Sunderland is at Bolton, Stoke travels to Crystal Palace, Queens Park Rangers takes on West Bromwich Albion, Norwich is at Peterbrough, and Wigan hosts Bournemouth.
In an all-Premier League meeting on Sunday, Arsenal has a trip to south Wales to face Swansea for the first time since losing to them in the league last month.
In Monday's final third-round match, Everton travels to fourth-tier club Cheltenham.