Group A

Mahmudullah - Bangladesh

Until the 2015 World Cup, most opposition resources would've been focused on shutting down Tamim Iqbal, Shakib Al Hasan and Mushfiqur Rahim. Mahmudullah's progress since making Bangladesh's first World Cup century against England last March hasn't slowed down. Most recently, he has reeled off 114 runs in his last four T20I innings without being dismissed, scoring off 76% of his deliveries in that stretch to prevent any pressure from building, and has the most sixes in T20s for Bangladesh, with 25.

William Porterfield - Ireland

Though never a headline grabber in the Ireland side, the captain has been one of his country's most valuable assets, particularly in T20 cricket. Porterfield is the only player to score a T20 century for Ireland, with his 127 not out coming against USA at the 2013 World T20 Qualifier. In almost anonymous fashion, he sits atop Ireland's run charts in T20 cricket, with 1497 runs at 25.81, more than 200 clear of Paul Stirling. Including Ireland's two unofficial warm-up matches ahead of this tournament, Porterfield has scored 421 runs at 42.10 in his last 13 T20 innings at a time when Ireland's overall batting unit his struggled.

Stephan Myburgh - Netherlands

Names like Ryan ten Doeschate, Dirk Nannes and Tom Cooper might be more prominent in the annals of recent Netherlands cricket history, but Myburgh has been a force at the top of the order since making his T20 debut for them in 2012. He is Netherlands' all-time leader in T20 runs with 1199, half-centuries with 11, and sixes with 50. He'll play a central role if Netherlands are to repeat their qualifying heroics from 2014.

Aamir Kaleem - Oman

This left-arm spinner could become the tournament's biggest hero ... or villain. It all depends on which side of the mankad debate you are on. Kaleem set off a firestorm during the qualifying round of the Asia Cup when he ran out Hong Kong star batsman Mark Chapman for creeping out of the non-striker's crease. Scotland's Rob Taylor tweeted about an unnamed Oman bowler attempting it against them in a warm-up match on Friday. Don't look away, or leave your crease early, when Kaleem comes on to bowl.

Group B

Najibullah Zadran - Afghanistan

Former coach Andy Moles famously characterized this middle-order batsman as someone who "can't block the ball to save his life". That isn't so much of a concern in T20 cricket. The 23-year-old's kamikaze-style batting is a left-handed mashup of Shahid Afridi and Glenn Maxwell. Never one to play for his average, Najibullah still claims a robust mark of 27.21 in 20 T20Is, nearly eight runs higher than his mark in ODIs. Fans may want to get the hard hats out in the stands if he gets going.

Ryan Campbell - Hong Kong

The oldest player in the tournament at 44, former Australian international Campbell has been playing on the Hong Kong domestic scene for the past several years. In his second warm-up match for Hong Kong in India, he top-scored with 46 and took 2 for 10 in three overs of offspin. It's been 10 years since he played his last professional match for Western Australia in the Sheffield Shield, but Campbell might just have a few gallons left in the tank.

Matt Machan - Scotland

The left-hander has only played 16 T20s for Scotland, but his eye-popping average of 39.69 is seven runs better than his nearest team-mate. Already, he is fifth on Scotland's run list with 516 and reaches fifty once every four innings. In their last T20I before the tournament, Machan top-scored with 43 in a win over Netherlands in Dubai. His part-time offspin may be vital as well at this tournament in support of newly-minted lead spinner Mark Watt.

Hamilton Masakadza - Zimbabwe

The captain's 1425 T20 runs for Zimbabwe are more than twice as many as the next-closest active player, Elton Chigumbura. He also holds the marks for highest individual innings for Zimbabwe, set two months ago with an unbeaten 93 off 58 balls in Khulna against Bangladesh, and most career sixes with 47. Heading into this tournament, his bat is smoking hot. Last month he struck 162 not out off 71 balls for Mountaineers in a domestic T20, and an unbeaten 68 off 49 in a warm-up win over Ireland on March 7, including six sixes.

Peter Della Penna is ESPNcricinfo's USA correspondent. @PeterDellaPenna