Five matches, five defeats. That's how a promising Royal Challengers Bangalore season ultimately came to nothing. In each of those last five games, the Royal Challengers batted first, posting totals of 145, 164, 120, 152 and 131. And as hard as their bowlers tried to keep them in the game, they simply didn't have enough runs to defend, with only two of these matches going into the final over.

Something, clearly, went horribly wrong with the Royal Challengers' batting. But what, and why? How did a team that won seven of its first ten games disintegrate so spectacularly?

According to Mike Hesson, the Royal Challengers' director of cricket, the downturn was caused by the batsmen's inability to adapt to the slowing down of the pitches as the tournament progressed.

"The reality is that the wickets slowed up and as a batting group we didn't adapt quickly enough, and when you don't score enough runs you put an awful lot of pressure on your bowling unit," Hesson said in a media interaction on Saturday. "Last five games, we batted first, [and] on all of the surfaces we struggled to adapt, we struggled to be able to apply any pressure on our opposition, we kept losing wickets by trying to force our case, therefore you end up basically crawling over the line a little bit from a batting point of view, getting a sub-par score, and then scrapping hard.

"And the fact that we've had to scrap for every game, the last four or five, it certainly exposed the fact that we struggled on the slower surfaces as the tournament progressed.

"The first ten rounds, when there was enough pace in the surfaces, as a batting unit we were very good. In the death we were the second-best team, in the powerplay I think we were second or third, in the middle we were sort of around the middle, and as the tournament progressed we dropped off in those phases, but that in a nutshell was the story of the last five games."

On the surface, Hesson's reading seems accurate. The Royal Challengers were indeed the second-fastest-scoring team in the death overs until the end of their tenth match of the season, and third-quickest in the powerplay, but second-from-bottom in the middle overs.

Then they simply fell off a cliff, particularly in the death overs (their middle-overs scoring rate actually improved marginally in the latter part of the tournament).

But did cracks suddenly erupt in the Royal Challengers' batting unit after game 10, or did they exist right through the tournament, papered over initially by the acts of a genius? Look at the death-overs numbers in the above graphic, and think about this game, this game, this game and this one. Would the Royal Challengers have won any of them without AB de Villiers?

Four wins out of seven, owing largely to the efforts of one man. And even de Villiers can't keep such a run of form going forever. The Royal Challengers' death-overs decline towards the end of their campaign can be attributed largely to de Villiers reverting to the mean. In their first ten games of the season, he batted six times in the death overs, and was only dismissed twice in 69 balls. In their last five games, he was dismissed three times in 16 balls across three innings.

A team can't be so reliant on one batsman. Or even two. Virat Kohli's approach in T20s has been widely debated, but when he makes it as far as the death overs he usually makes it count. In the early, happy phase of the Royal Challengers' season, he made it into the death overs four times in 10 innings, and scored 88 runs off 40 balls (strike rate 220.00) while being dismissed once.

In his last five games, Kohli only got into the death overs once, scoring 17 off 11 balls in the phase against the Chennai Super Kings, after having scored 33 off his first 32 balls.

That sort of start was typical of Kohli's season, and the Royal Challengers were prepared to accept it given the death-overs payoff he can deliver. But did they organise the rest of their batting well enough to complement those slow starts?

Simon Katich, their head coach, certainly believes so.

"One thing that we tried to do with our batting order was structure it so that guys who batted in consistent pairings complemented each other," Katich said. "You're having guys who are strong against maybe pace, and other guys who're strong against spin to complement each other in different phases of the innings, so it makes it harder for opposition captains to really stifle the innings.

ALSO READ: Gambhir says RCB need to look beyond Kohli for captaincy

"We see that in games where two similar players bat together and an opposition captain can win a three- or four-over spell of the game with a certain type of bowling, so we were really mindful of that, and hence the reason why there were games where we did bring left-handers into the fold to break up our right-handers at the top, which we obviously had, with three of the top four, in [Aaron] Finch, Kohli and de Villiers.

"Pretty much in T20, batting has to be adaptable and flexible, because the nature of the game situation dictates how you have to play, whether you're batting first or you're chasing and when you enter the fray. So there are no actual set positions in T20 a lot of times, it comes up to how you have to go against a certain match-up and try and make it as hard as possible for the opposition captain."

That flexibility, however, wasn't always apparent when it came to de Villiers' batting position. He batted at No. 4 in all but two of his innings, no matter when the second wicket fell. And he ended up with a rigidly fixed position over his last six innings of the season, after the Royal Challengers made the widely debated decision to promote a pair of left-handers, Washington Sundar and Shivam Dube, above him, to match up against the two legspinners in Kings XI Punjab's attack.

"We certainly tried [promoting the left-handers] in Sharjah against Kings XI knowing full well they had their two legspinners bowling in that phase of the game," Katich said. "Unfortunately, the execution of that plan probably meant that we copped a lot of flak over it, because it left AB de Villiers not batting as much as we would have liked, and also we didn't get the runs we would have liked in that phase, where we did promote Sundar and Dube. I don't think there was anything wrong with the actual thought around the plan."

"The wickets slowed up and as a batting group we didn't adapt quickly enough, and when you don't score enough runs you put an awful lot of pressure on your bowling unit"
Mike Hesson, RCB's director of cricket

There wasn't, but the flak they copped for the move dissuaded the Royal Challengers from trying it again, even in situations that seemed to cry out for it.

In the game against the Super Kings in Dubai, Kohli and de Villiers scored a combined 68 off 62 balls against Ravindra Jadeja, Mitchell Santner and Imran Tahir, all of whom turn the ball away from the right-hander. Moeen Ali, a left-hand batsman with a T20 strike rate of 169.36 against legspin and left-arm orthodox before that game, and a far more proven performer than Sundar or Dube, didn't come out to bat until the 18th over.

Moeen didn't play another game until the Eliminator against Sunrisers Hyderabad, when the Royal Challengers made two major changes to their batting line-up. It felt like a belated recognition of the issues that had plagued the team through the tournament, especially through the middle overs. Kohli, who had struggled to find the boundary through the middle overs all season, opened alongside Devdutt Padikkal to try and make use of the powerplay field restrictions. Moeen - who boasted the best middle-overs strike rate (176.51) of all Royal Challengers batsmen since the 2018 season - came back into the team.

According to Katich, Moeen was set to bat at No. 3 to target the legspin/left-arm spin combination of Rashid Khan and Shahbaz Nadeem. But the Royal Challengers lost two wickets within the first four overs, and the plan was put on ice. Moeen eventually arrived in the 11th over and ran himself out, off the first ball he faced - a free-hit.

ALSO READ: Kohli's mentorship and never-say-die attitude vital for RCB, says coach Katich

"There was a period, if we hadn't lost a wicket early [in the Eliminator], Moeen would have probably batted three, if he'd come in at the back end of the powerplay or just after the powerplay, so the timing of the wickets probably changed how our batting line-up looked," Katich said.

"We were taking the aggressive option, really, in moving Virat to the top of the order to try and get him in the game, to influence the game positively. That didn't happen, I mean, that's the way it panned out. It's not often you get someone [Kohli] caught down the leg side and someone else run out off a free-hit no-ball, so that's the way the game goes sometimes, and it didn't go our way."

It didn't go their way, but it might well have done had the Royal Challengers taken those decisions earlier in the tournament, and acted more proactively to address their middle-overs issues.

Karthik Krishnaswamy is a senior sub-editor at ESPNcricinfo