England rugby have been dealt a huge blow ahead of the Women’s Six Nations with centre Tatyana Heard ruled out of the tournament.

The World Cup winner has been John Mitchell’s first-choice inside centre throughout his tenure and started the final against Canada at Twickenham in September.

Heard has suffered a foot injury, though, that will sideline her for the entirety of the Six Nations campaign and leaves the Red Roses relatively short of proven options in midfield.

Veteran Emily Scarratt retired after the World Cup and is now part of Mitchell’s coaching team, while Heard’s club-mate Jade Shekells is currently out of action.

Uncapped Loughborough Lightning midfielder Carmella Morrall has joined the squad and could vie with fellow potential debutant Sarah Parry for a place alongside captain Meg Jones.

Fly halves Helena Rowland and Holly Aitchison are also capable in either the No 12 or No 13 shirts, while Mitchell has floated the possibility of experimenting with full-back Emma Sing in the centres.

“We’d like to see how Emma Sing goes in the midfield over the next few years,” the England head coach explained. “I think it is important for her to develop another position because she is a very strong carrier of the ball.

“Whether we look at that in this tournament is another thing, but it’s certainly in our minds. Emma could play 12 or 13. It’s something that Emma is also pretty keen on developing, and it allows her to contribute to the group and add another string to her bow.”

England open their campaign against Ireland at Twickenham’s Allianz Stadium on Saturday 11 April. More than 70,000 tickets have been sold for the game.

The usual occupiers of the Tottenham Hotspur Stadium have spent this season bemoaning the under-performance of a highly-talented, highly-paid squad, and there will have been plenty of occasions where the Saracens faithful would have joined in that Spurs refrain. The north London rugby club are not nearly as lowly as their Premier League counterparts – and there is no longer the threat of relegation for any team in the Gallagher Prem – but with their play-off hopes in real peril, a narrow defeat to Northampton Saints in their annual visit to this glimmering sporting cathedral was most unwelcome.

The 21-17 defeat here, sealed three minutes from time by Archie McParland’s second score, leaves Saracens 12 points off Exeter Chiefs in fourth, a gaping chasm to make up with just six Prem games to come. And so, too, were a few of the league’s fears creeping nearer: Bristol’s shock defeat to Harlequins in Cardiff has opened a gap between the four best and the rest. While the Bears will surely still have a significant say, a petering towards the play-offs is, at the very least, a possibility for a league that has of late been proud of its competitive balance.

The truth, though, is that too many sides have not been consistently at the level required, with Saracens very much among them. The stakes, the stage, and the circumstances of it being director of rugby Mark McCall’s last season provided plenty of reason for a strong showing; they were much, much better here than they had been in a drubbing at Bath last week, but a few key errors and a sluggish start cost them.

“It is absolutely gutting to lose, but I’m not gutted with the way we lost,” said McCall. “To go 14-0 down so early after losing by 60 points last week, the way we fought our way back into the game was magnificent, really, and I am actually really proud of the performance given what happened last week. It’s gutting to lose it at the end, but we can work with that.

“Although we lost tonight, we were two minutes away from having a really happy changing room. I know there is something good to build on.”

While this is a place that does pomp and circumstance well, the match, hard-fought though it was, did not live up to the bonkers billing it had been given by pre-match entertainer Dizzee Rascal. The cast list was impressive on both sides of the team sheet, with a scan down the Saracens side perhaps making one question their somewhat modest state. Even without Ben Earl and Juan Martin Gonzalez, there were 10 full internationals in their starting side and another six among the replacements. Any club that boasts Maro Itoje, Owen Farrell, Elliot Daly and Jamie George should not be questioning a lack of leadership as often as Sarries seem to have been this season.

McCall had termed this a must-win game to preserve their fading hopes of a top-four finish but did not get the sharp start he would have desired. A series of errors, which began virtually from the kick off, meant Saracens spent most of the first 20 minutes inside their own half, or, at best, losing the kicking exchanges near halfway. Only some strong defensive work on the goalline denied Henry Pollock an instant impact but it wasn’t long until Tom Litchfield finished off a vibrant Saints move.

Those Saracens leaders looked a little leggy and lost. Daly – fresh from putting pen to paper on a new deal at the club – was twice sat down by James Ramm defending the right edge, while Farrell failed to find touch from a free kick. McParland, the bright young scrum half, soon added Northampton’s second.

Slowly, though, the “home” side warmed to the grand occasion. A jinking Tobias Elliott got them on the board, before Saints lost their fly half and much of their control: Fin Smith’s failed HIA forced a reshuffle with Furbank taking on lead play-making duties. They survived with a one-try lead intact to the interval but not long thereafter as Theo Dan’s thumping finish and a Farrell conversion levelled the scores.

They might have been ahead if not for a desperate Pollock intervention on fellow blond bombshell Hugh Tizard as the Saracens lock took partner Itoje’s pass over the line. Level, then, it remained through much of a sloppy and scrappy second half in which neither could find any sort of fluency. Farrell missed touch again, this time with a penalty to the corner, before being replaced by Fergus Burke.

The bull-like Northampton replacement JJ van der Mescht threatened to break the tie through sheer force, only hauled back by a herculean effort from Elliott and Burke, which allowed the latter to nudge his side ahead from the tee with eight minutes to play.

Burke was not done there, somehow quelling Van der Mescht’s might for a second time, but he was powerless to stop what proved the match-winning score. A tiring Saracens edge defence faltered as Litchfield burst into space before producing a deft back-door offload to an arriving McParland – the bong of Big Ben that marked full time might too have been the death knell for Saracens’ chances of a top-four finish. While there have been bright spots this season – the Investec Champions Cup win over Toulouse stands out – a tricky trip to Bath next Saturday could well end their European adventure, too.

There was brighter news for the club in the first half of the double-header as their women decisively dismissed play-off hopefuls Sale Sharks 54-0 in Premiership Women’s Rugby (PWR).

Saracens, steered superbly by Liv Apps and Zoe Harrison in the halves, blew away their opponents to bounce back from defeat to unbeaten table-toppers Gloucester-Hartpury in their last outing, and look the likeliest side to deny the league leaders a fourth consecutive title.