1. Sunil Narine - 66 matches, 85 wickets at 6.17 per overA mystery spinner who was barely known when Knight Riders bought him in 2012, Narine`s impact was instant, going on to win the Man-of-the-Series award in his first season in the IPL. The true value of Narine`s overs are evident when you consider that teams have scored at 8.02 runs per over in the time he`s been around, and the astonishing fact that 97 of his overs have come between overs 16 and 20.2. R Ashwin - 111 matches, 100 wickets at 6.55 per overAshwin sprang onto the scene in the third edition of the IPL, with match-winning spells en route to Super Kings maiden title, which earned him a spot in the Indian side for the 2011 World Cup. Over the years, he has gone on to become his captain Mahendra Singh Dhoni`s go-to weapon, be it with the new ball or in the death overs. In 2015, he finished an entire IPL season going at less than a run-a-ball, a rare achievement in the tournament`s history.3. Anil Kumble - 42 matches, 45 wickets at 6.57 per overAfter their disastrous start in 2008, The current India coach took over as Royal Challengers captain mid-way through the 2009 season and led from the front to take them to the final, with 21 wickets at just 5.86 runs per over, including a magical 5 for 5 spell on a difficult Cape Town track against Rajasthan Royals. Kumble went on to have yet another impressive season in 2010, before hanging up his boots before the 2011 auction.4. Glenn McGrath- 14 matches, 14 wickets at 6.61 per overA year after retiring from international cricket after winning his third World Cup title, and in the middle of his wife`s terminal illness, McGrath had one of the best seasons for a fast bowler in IPL history, picking up 12 wickets, including a match-winning 4 for 29 against Royal Challengers Bangalore. Despite being his side`s most economical bowler in the first season, McGrath was on the bench for much of the next season, before retiring from all competitive cricket.5. Lasith Malinga - 98 matches, 143 wickets at 6.67 per overThe IPL`s highest wicket-taker has also been among its most economical over nine seasons. Malinga`s wickets and tight bowling in the death overs have taken Mumbai Indians to two IPL titles, apart from two Champions League T20 trophies. His importance to the Mumbai side is exemplified by the fact that he remains one of the IPL`s few single-franchise players, alongside team-mates Harbhajan Singh and Keiron Pollard, retained by Mumbai every time so far.6. Muttiah Muralitharan - 66 matches, 63 wickets at 6.67 per overMuralitharan was purchased for a relatively cheap $600,000 in the inaugural auction, and never failed to live up to his reputation through his first three seasons for Chennai Super Kings, putting in crucial performances en route to their two IPL titles. His miserly bowling performances were a feature of his subsequent seasons with Kochi Tuskers Kerala and Royal Challengers Bangalore, before he retired in 2014.7. Dale Steyn- 90 matches, 92 wickets at 6.72 per overWhile Steyn`s performances have dipped of late, forcing him to warm the bench for Sunrisers Hyderabad last season, his overall economy rate of 6.72 is only testament to his value in his first six seasons. In 2013, his performances led Sunrisers to the playoffs in their maiden season, with 19 wickets at a sub-six economy rate, a rare feat for a fast bowler in the IPL.8. Roelof van der Merwe - 21 matches, 21 wickets at 6.74 per overVan der Merwe`s is perhaps the most surprising name on this list, considering he never found a place in the starting XI regularly for both his franchises. While his batting never took off, his left-arm orthodox kept things tight at one end. It is to his credit that, despite bowling most of his overs at the M Chinnaswamy stadium, he has managed an economy rate below 7.9. Daniel Vettori - 34 matches, 28 wickets at 6.78 per overVettori`s IPL career did not get off to the best of starts, often being forced to sit out at Delhi Daredevils. However, he came into his own for Royal Challengers Bangalore in 2011, picking up 12 wickets at 6.01 per over, captaining them to the final. He continues to be involved with the franchise as their coach, after retiring following a relatively average 2012 season.10. Mustafizur Rahman- 16 matches, 17 wickets at 6.90 per overAfter just one season, where he was often chosen ahead of the likes of Dale Steyn and Trent Boult, Mustafizur finds himself among the 10 most economical bowlers in IPL history. He was named the tournament`s Emerging Player of the Season, as his bowling performances led Sunrisers to their first IPL title.Source: ESPNcricinfo