One week and 12 games into IPL 2018, a few trends have emerged. Here are the key ones, their impact on the results so far, and the effect they could have on the rest of the tournament.

Run Rates in the first over and Powerplay are at an all time high in the IPL so far ESPNcricinfo Ltd

Attacking the first over

Until last year, the first over used to be one of the least expensive in an IPL innings, but that is no longer the case. Teams have realised the need to attack from the start. The average run rate in the first over this IPL season has been 8.70 - easily higher than in the first 12 games of previous seasons. The average run rate in the first over in the 2017 season was only 6.53. On five occasions already (till April 15), teams have scored more than 14 in the first over; that happened only twice last year.

A team that has not suffered an expensive first over is Sunrisers Hyderabad. Their attack has bowled three of the five most economical first overs this season, a reason they have won all three games.

Plenty in the Powerplay

Batting teams have tried to maximise their returns from the Powerplay in the first 12 games. The average run rate in the first six overs this season is 9.38; the highest Powerplay run rate after 12 games in all previous seasons was 8.33 - in 2017. Teams haven't lost many wickets in the Powerplay this season either: the average runs per wicket is 36.51 so far, the highest at this stage among all editions.

Not only is this approach evident in the first innings of the game but also while chasing - irrespective of the target. The average Powerplay run rate in the second innings is 9.55. Nine out of 12 matches have been won by the chasing team and the match has usually been decided in the Powerplay.

The middle-over problem

A reason teams batting first have struggled this season is because they lose their way in the middle overs. On more than one occasion, teams have looked good for high totals but fallen short by 15-20 runs. The average run rate in the middle overs batting first is 7.64, and teams average 22.32 per wicket.

Breaking it down further, teams have scored only 7.13 per over between overs seven and ten, and 8.11 between 11 and 15. The dip in run rate between overs 7 and 10 is largely because several wickets have fallen in the sixth and the ninth overs and impacted the scoring rate.

The two times teams scored more than 200 was because of extraordinary hitting at the finish from KKR's Andre Russell and Royals' Sanju Samson. Royals scored at 8.55 per over in the middle phase of their innings against Royal Challengers Bangalore, but lost only two wickets and were able to leverage that platform to score 88 runs in the last five overs to reach 217. Teams batting first can't always expect a flurry of runs at the death, and so they need to do better in the middle overs, especially between seven and ten.

For example, Kings XI had an extraordinary Powerplay against CSK, scoring at 12.5 runs per over, but then lost four wickets and scored at 8.77 in the middle overs. Not having a finisher, they managed only 43 runs in the last five overs and fell short of 200.

Googlies have been the flavour of the first week for the spinners ESPNcricinfo Ltd

Done in by the googly

Mayank Markande, R Ashwin, Mujeeb Ur Rahman and Sunil Narine are some of the spinners who have excelled in the first week of the tournament. One delivery that has been especially effective is the googly.

Virat Kohli and MS Dhoni have been victims of the wrong 'un, and the spinners have used this delivery liberally. By the end of the first week, 194 googlies had been bowled for 13 wickets and 232 runs. Markande used the googly better than anyone else, taking five wickets at an economy rate of 5.75. A lot of Indian domestic batsmen have struggled against the googly; they average 18 against the googly, while international batsmen average 15.

Facing Googlies Runs Balls Outs SR Indians 125 108 7 115.7 Overseas 103 93 7 110.8

DRS makes its debut in the IPL

The Decision Review System was introduced for the first time this IPL, and it has made a difference. Ashwin used the DRS at a crucial juncture against CSK, when the umpire signalled four runs despite Sam Billings having been hit on the pad. Mumbai Indians also used it successfully against Sunrisers' Kane Williamson to take that game to the final over. From the data of the first week, most teams seemed to have used the system efficiently.

KKR, however, have been on the wrong side of the system, with no decision going their way so far.