Ryan Bertrand is in contention to face former club Chelsea when Southampton host the Blues on Super Sunday, live on Sky Sports 1 HD.
The England defender is returning from a hamstring injury suffered on international duty, and could slot straight back into Claude Puel's back-line.
Southampton, who boast the joint-second best defence in the Premier League, have lost just once in their last 10 matches, a narrow 1-0 defeat to Inter Milan at the San Siro.
They progressed to the EFL Cup quarter-finals with victory over Sunderland on Wednesday, while Chelsea crashed out of the competition with a 2-1 loss at West Ham.
Despite the defeat, head coach Antonio Conte has pledged to keep faith with his 3-4-3 formation.
"I think it is the right way for the players because it is a good fit for the team," Conte said.
"We have found a good balance and also we have a good offensive situation because in every game we scored the goal.
"It is different when you defend with the four and when you defend with the three defenders but I see a lot of positive things."
Team news
Bertrand could return from a hamstring injury for Southampton, but Jay Rodriguez is a doubt after a clash of heads against Sunderland. Fellow striker Shane Long is still out with a hamstring problem.
Fraser Forster, Virgil van Dijk, Steven Davis and Charlie Austin will be among the players who return after being rested against the Black Cats.
For Chelsea, John Terry is likely to return to the substitutes' bench.
Terry made his first start in more than six weeks following an ankle injury as the Blues made seven changes for their EFL Cup defeat at West Ham, but Conte is set to recall many of the players involved in last Sunday's comprehensive win over Manchester United.
Branislav Ivanovic is available and Kurt Zouma is nearing a return from his long-term knee injury, but playmaker Cesc Fabregas (thigh) remains out.
Opta stats
Southampton have won just two of their last 14 top-flight games against Chelsea, though did beat the Blues in October 2015 (D5 L7).
Chelsea have lost just one of their last eight visits to Southampton in the league (W5 D2).
Since a 2-1 defeat to Chelsea in February last season, the Saints are unbeaten in nine home Premier League games (W6 D3). It is their longest home unbeaten top-flight run since March 2005, when they went 12 games without defeat.
The Blues have won their last three league games, and they will be looking to make it four in a row for the first time since April 2015 when they were on their way to winning the title.
Only Liverpool (59) have had more shots on target this season than Southampton (55), with Chelsea in third (54, level with Spurs).
Nathan Redmond has scored in back-to-back league games for Southampton - he's never scored in three successive Premier League matches.
Eden Hazard has already equalled his goal tally from last season (four in 31 games) from just nine appearances this season.
Merson's prediction
I'm surprised Chelsea went out of the EFL Cup in the manner they did. They're playing once a week and should have highlighted that as a must-win competition. They missed a trick there.
Puel's side will put up a real fight on Sunday because they are extremely difficult to break down and a threat going forward.
I'm picking a draw but if Chelsea do manage to get a win at St Mary's, you need to put them back up as contenders.
PAUL PREDICTS: 1-1 (Sky Bet odds 5/1)
Betting
Southampton are the 21/10 outsiders with Sky Bet to win at home to Chelsea in Super Sunday's second match despite their strong run of form.
Saints are unbeaten in their last five league games but resurgent Chelsea are on offer at 13/10 to get the victory. The draw can be backed at 23/10.
Chelsea walloped Manchester United 4-0 last Sunday and a repeat of that convincing scoreline can be backed at 50/1. Blues striker Diego Costa is the 4/1 favourite in Sky Bet's first goalscorer odds and the in-form Austin is the top Southampton contender in that market at 11/2.