Varun Aaron is quick. On Wednesday at the Khan Shaheb Osman Ali Stadium, he maintained an average speed of 88.2mph, and his fastest delivery clocked 93.2mph on the speedgun. That's 149.99kph. India have a fast bowler. A genuinely fast bowler.

It wouldn't be inaccurate to say that the selectors gave Aaron a chance to play for India solely because he was quick. He made his ODI debut in October 2011 and his Test debut a month later. At that point, he had taken 26 first-class wickets in 12 matches at an average of 41.50. His last first-class match before his international debut was for Rest of India against Rajasthan. In that match, he took one wicket for 117 runs in 42 overs.

He didn't have the numbers in first-class cricket to suggest he could take wickets at the international level. He had, however, sent the speedgun needle into previously largely uncharted territory for Indian fast bowlers. You could legitimately label him "right arm fast".

On Wednesday, Aaron came on with Bangladesh 40 for 1 in 11 overs. Bhuvneshwar Kumar and Mohammed Shami had bowled tight first spells, and each of them had produced edges that flew through gaps in the slip cordon. There was little in the pitch to enthuse the seamers, but they had kept the batsmen under pressure.

Aaron immediately released it with his first two balls, wide half-volleys that left-hand batsman Mominul Haque drove handsomely for fours. This was a portent of what was to come, although it wasn't immediately apparent, after R Ashwin dismissed Mominul at the other end and Aaron bowled a quiet second over.

You could tell even then, though, that he wasn't really worrying Anamul Haque and Mushfiqur Rahim. His length wasn't asking them any difficult questions, and both batsmen came forward and drove him confidently. For now, they were hitting to the fielders.

What came next was unexpected. Out of nowhere, in Aaron's third over, Anamul jumped down the track and clattered him over long-on for six. In his fifth over, Anamul charged him again. Aaron banged the ball in short. Anamul swatted it for six. Later in the over Aaron served up another half-volley. Anamul clumped it back past him for four.

Aaron was bowling fast, but there was no extra ingredient - no cunning and no intimidation either. Even that can work sometimes, if you bowl fast and attack the stumps, but Aaron's default line was fifth or even sixth stump.

When he came back on later in the innings, in the 37th over, Aaron dismissed Anamul, bowled off his inside edge, but only after he had struck two more fours, the second a slash past point off a high full-toss that was called no-ball. In his next over, the high full-toss made another appearance, seemingly slipping out of his fingers and striking Mushfiqur Rahim a painful blow on the chest. The second offence meant he had to go out of the attack.

It was unlikely he would have done any more bowling after that over anyway. Before being struck by that beamer, Mushfiqur had spanked Aaron for two more fours and a six. All of that had left him with figures of 1 for 74 in 7.5 overs. This was the second time that Aaron had gone for more than eight runs an over in an ODI, and this was just his eighth match. His career economy rate had now spiked to 6.64.

India's excitement with Aaron's pace is understandable. It's a precious resource. And he has improved his bowling to the extent that he has enjoyed his best ever first-class season after recovering from recurring back injuries. But he still seems unsure of what exactly he's trying to do when he bowls at the international level. It has been the same case with Umesh Yadav, and it's hard to tell if either of them is getting the guidance they need to make the most of their talent.

It's hard to tell if any of India's young fast bowlers are getting this. Aaron's spell in Fatullah was the 12th instance of an Indian fast bowler conceding eight or more runs per over in an ODI spell of six or more overs since the start of 2013. Umesh Yadav and Mohit Sharma appear once each on that list. Vinay Kumar and Mohammed Shami, like Aaron, have two entries each, while Ishant Sharma features a staggering four times. All of this, remember, has happened in the last 14 months.

In that period, India's batsmen have been made to chase 300-plus targets eight times. They've been made to do it not just in Jaipur, Nagpur and Rajkot but also in Johannesburg, Kingston and Wellington.

Despite Aaron's waywardness, their target in Fatullah was "only" 280 and they got home without too much fuss. It's what Virat Kohli does. But he must wish sometimes that he didn't have to do it so often. He will wish he won't have to keep doing it in this tournament. MS Dhoni isn't around to help him.