Mumbai Indians' WPL 2026 campaign has been quietly eroding in the first-six overs game after game.

Four losses in the league stages are a tournament first for the two-time champions who came into the fourth edition, following a mega auction, with nearly the same title-winning squad in tow. Yet, the season has unraveled with one disturbing pattern: across the six games, their batting PowerPlays have dictated terms - and almost always against them.

Even before isolating MI, the winning teams in WPL 2026 are averaging 45.46 runs per wicket at 8.74 runs-per-over in the PowerPlays. In defeats, the numbers plummet to 23.17 at 6.83 RPO. The margins have proved decisive, and Mumbai have consistently been landing on the wrong side of it.

The contrast was stark against Delhi Capitals on Tuesday: Mumbai's 23/2 vs Delhi's 57/0 despite the shift from Navi Mumbai's flat tracks to their first game of the season on Vadodara's tricky surface. In the batting phase that's increasingly starting to dictate outcomes in WPL, MI surrendered before even before the game could settle.

Across their six completed games thus far - one more than all of the other four - MI have scored at a concerning 6.05 RPO in the PowerPlays - the least impressive returns in the competition. That number looks bleaker in context when compared to the table-toppers RCB who are operating at 8.45 while bottom-dwellers Gujarat Giants are paradoxically the most aggressive upfront, at 9.03 RPO. At only a touch above run-a-ball for six games now, the defending champions are simply below par.

Conditions are part of the explanation but, like skipper Harmanpreet Kaur conceded after the loss to DC, should not be the excuse. Seamers, across teams, were notably more effective in the Navi Mumbai leg, and that trend has carried to the second half of the competition, in the slightly colder climes of Vadodara. Yet MI haven't adapted well.

Against pace/seam, Mumbai have the lowest batting strike-rate and the lowest run-rate this edition. Already in the playoffs, RCB, by contrast, are comfortably ahead at 140.28 SR and 8.41 RPO, emphasising just how of this is to do with the approach rather than conditions alone.

Teams in PP vs pace/seam in WPL 2026

Historically, across the four seasons MI have only won eight out of the 17 games (win% 47.06) they've batted first in. They've been very good chasers though, with their win% soaring to 77.78 - that is 14 successful run-chases in 18 attempts. This season alone, three of the four defeats have come while batting first, only one of which was a narrow last-ball decider.

This failure to maximise the PowerPlay in conditions assisting seamers has often seen MI middle-order playing catch-up, forcing consolidation from their most experienced pair of their captain and vice-captain instead of acceleration. Harmanpreet Kaur (166 at 155.14 SR) and Nat Sciver-Brunt (136 at 161.9 SR), in fact, have the most number of runs against spinners in this edition. Incidentally, they are also the season's top-two run-getters, but all that while repairing the innings that led to competitive, but rarely commanding, totals. By their own admission, MI fell 20 short against DC who chased down the 155-run target with an over to spare.

"We were 20 runs short with the bat, and even in the PowerPlay, we were not able to execute with the bat and ball. I think that is something which is really bothering us throughout this tournament. And we need to really push ourselves when we are batting in the PowerPlay," Harmanpreet said in the post-match presentation.

Now, a big part of this PowerPlay paralysis also appears self-inflicted, stemming from a combination of tactical misjudgments and forced changes due to availability and fitness concerns. Stability across the line-up, role clarity, and continuity has been a hallmark of Mumbai's success in the inaugural WPL cycle. This year, all of it has been conspicuously missing.

When MI decided to retain the 17-year-old G Kamilini - a like-for-like left-handed wicketkeeper-cum-opening batter - ahead of their seasoned but injured opener Yastika Bhatia, the succession plan seemed clear. They had, after all, already retained another injured overseas opener in Hayley Matthews who, through a shoulder surgery, had had no game-time in the lead-up to the season. So, Kamilini was set to open alongside Matthews, providing continuity if not a lot of big-stage experience.

That plan unravelled almost immediately when the Caribbean star's return was delayed due to a quad niggle. This prompted MI to open with Amelia Kerr, perhaps encouraged by her recent success as an opener in Super Smash back home. Kerr - MI's regular no. 5 and a pivotal part of their vaunted middle-order - was clearly a stop-gap arrangement, but failed to get going in two chances and the early setbacks MI suffered reflected the discomfort.

Before Matthews was deemed match-fit, Sciver-Brunt fell ill. While that allowed MI to persist with their top-performing allrounder in Nicola Carey and also welcome back their regular opener, the musical chairs among their overseas-four combination continued. Despite an impact knock in her first game back, Matthews was "rested" when the vice-captain returned next match, meaning another tweak of the opening combo. Enter Amanjot Kaur; and MI's search for a functional opening combination dragged on.

By the time Matthews returned again, in Game 5, Kamilini's returns dwindled since the 32 in the tournament opener and MI appeared to have lost confidence. The teenager was pushed down the order at 8 (before eventually getting ruled out of the season with a shoulder injury), while S Sajana was handed a promotion. That was Mumbai's fourth different pairing at the top of the order in the home leg alone. Conscious of this churn that's very unlike MI, the team persisted with the same combination in Vadodara, but the results were familiar, and disappointing. At 21/2 at the start of the fifth over, the PowerPlay had once again slipped away early to effectively seal the fate of the contest.

"Our PowerPlay with the bat hasn't clicked," head coach Lisa Keightly, too, admitted. "Obviously, we've tried a few combinations and Hayley being injured at the start of the competition, [we] probably didn't get off to the start we wanted... and now we're three-quarters of the way through the competition and we've found it hard to get going in the PowerPlay. We've always sort of been behind, probably, where we'd want to be at that stage and then it obviously puts a lot of pressure on our middle-order coming in.

"Melie, we know she's probably very valuable in the middle - more so than in opening. So, she was just filling the spot for Hayley. And then with Kamalini - and it looked like she had lost confidence, I suppose, in the PowerPlay so we were trying to move her down - she's only 17 - so to help her get going again into the competition [before she got ruled out]. So, we've had to have batters up in the PowerPlay that, if we were fully-fit [squad] when we started the competition, I don't think you would have seen as many changes. We're working hard to try and get that combination, and get it going. We've tried to leave Sajana there the last-two times because we're aware that we've had a lot of combinations and we desperately want one to click and to get us a good start," she added.

All combined, none of the five openers - tried in different combinations - have managed to cross 40 in any innings. What this frequent chopping and changing has done is made MI take a more reactive than proactive approach, with the roulette not just disrupting individual rhythm - as in the case of Kerr and Kamilini - but also blunting out their intent and strategies in that crucial phase with the bat. For a team built on clarity and continuity, this common denominator in the losses feels as unsettling as it is unfamiliar, and it explains why their PowerPlay problems are as much tactical as they are statistical.

Despite unprecedented losses, MI are holding on to the second spot in the table due to a superior NRR. But here's the caveat: with two league games left in the tank - one fewer than the other four - Mumbai's margin for error is significantly lower. And unless their PowerPlay stabilises soon, the mettle of their middle-order may no longer be enough to keep their campaign alive.