With midweek matches taking place for the first time, the play-off picture in the Premiership has become clearer over the past week, but Exeter continue their march to Twickenham.

Here are some of the talking points from the last seven days.

Disciplined Sale turn play-off hopes around

This time last week, Sale boss Steve Diamond admitted his side's top four hopes were going up in smoke after a poor start to the resumption.

His players' response has been resounding; a hard-fought victory at Wasps followed by a 40-7 thrashing of a weakened Bristol firmly re-establishing the Sharks' top four credentials.

Part of the turnaround has been down to discipline, with desperate times calling for desperate measures.

"We gave five penalties away [against Bristol], we gave 12 away on Tuesday [against Wasps], we gave 23 away [against Exeter] and 18 the week before [against Harlequins]," said Diamond.

"We are learning and getting better."

Four rounds into the restart, and the play-off picture is starting to take shape, with Northampton dropping back, and Sale, Bristol, Bath and Wasps seemingly competing for three spots.

But regardless of the scrap for the top four, Exeter's dominance of the league shows no sign of abating. Their victory at Bristol, with a much-changed line-up, was a remarkable show of character, composure and squad depth. They then followed that up with a nine-try demolition of Worcester on Sunday. It will take something special to stop a Chiefs' title procession.

Saints selection policy stands out

While there have been a handful of gripping games since the resumption, squad rotation and the lack of a relegation threat has resulted in a number of mis-matches, which does little for the integrity or reputation of the Premiership.

Exeter and Saracens have the quality and depth to compete regardless of their rotation, but many clubs at the moment are waving the white flag with their team selection.

One interesting exception is Northampton, with Chris Boyd choosing to mix and match his players, fielding two completely separate sides of similar standard over the first four rounds of the restart.

In terms of results, it hasn't worked, with the Saints losing three out of four - including Sunday's match at Harlequins - and dropping away from the title race.

But all four of Northampton's matches have been close and competitive. While Boyd may not have endeared himself to Saints fans, neutrals should feel differently.

Meanwhile, fans frustrated with one-sided games should focus firmly on the Pro 14 this weekend.

Both Leinster against Munster and Edinburgh against Ulster will be full-blooded affairs between full-strength sides although - as with Exeter in the Premiership - it's hard to see anyone but Leinster winning the league and retaining their title.

Extra matches = less training

With some clubs set to play as many as seven matches in a month, Premiership Rugby is in the midst of its most relentless schedule in history, with clear player welfare repercussions.

However, Sale boss Diamond says the strain of the extra matches is being offset by a drastic decrease in training load.

"Between games at the moment we watch a video and then do a [pre-match] walk-through," he told BBC 5 live.

"So the training in the week has gone to zero, so the amount of stress their bodies are taking is less than it normally is."

While it would be dangerous for this congested schedule to be repeated on a regular basis- it is a one-off, short-term fix because of the coronavirus pandemic - the medical data will make fascinating reading.

Clubs and unions worldwide have been implementing individual player passports, monitoring their loads in training and matches, so each player can be treated and managed accordingly.

World Rugby boss Brett Gosper raised some eyebrows when he told us last week the game has never been safer given the improvements in technology and injury management.

But while there is a long, long way to go, medical advancements coupled with law changes designed to make the game simpler and safer, might start to solve an issue that has blighted the game throughout professionalism.

Summer rugby the future?

While regular midweek matches alongside weekend games is probably unreasonable on welfare grounds, it is time the English clubs started to think outside the box.

Having originally been open to the concept of summer rugby, the clubs have performed a U-turn, putting a spanner in the works of a global calendar.

But isn't it time the Premiership stopped fighting a losing battle against football and the Premier League?

Regular matches through July and early August - during the football off-season - would give club rugby union in England priceless exposure, especially during quiet weeks in the sporting calendar. How good would Bristol against Exeter have been with a full house?

And on that note, should midweek games be embraced during international windows as well? It is nonsensical for the Six Nations, for example, to clash with the club game, as will be the case throughout the 2021 Championship.

As the RFU chief executive Bill Sweeney has said recently, it is time rugby union stopped competing with itself.

Time zones to dictate global links?

Twenty-five years on from the sport turning professional, rugby union is precariously (or excitingly, delete as appropriate) poised, especially with the coronavirus pandemic exposing fault-lines in the game and accelerating change.

Administrators have long suggested that rugby union will eventually become divided and governed not by hemispheres, but by time zones. Could this now happen sooner rather than later?

The prospect of South Africa and Argentina having a long-term future with Australia and New Zealand is now looking slim, with talk intensifying about South African franchises making a permanent move to the Pro14, while Australia and New Zealand are likely to further cement their links with Japan and the Pacific Islands.

With private equity companies tightening their commercial grip on the sport, rugby union is well and truly entering into a new era.