Over the last 7 years he has consistently been a quality bowler. He managed to get ranked as high as number 1 in the world in the ICC ODI bowlers rankings. (He is one of only 5 New Zealanders I can find to have done it, joining Hadlee, Bond, Vettori & Chatfield). His worst year in the last 7 was 2010 when he took 19 wickets in 13 matches at an average of 26.57 and an economy rate of 5.39. This gave him a bowling index score of 23.87. To put that in context Zaheer Khan has a career average of 29.03 and an economy rate of 4.91, (index 23.76). In Mills' worst year he was still as good as Zaheer Khan.
And yet we don't really like him. Nobody calls up talkback praising him. Nobody writes previews of series where he is seen as a threat. He just goes about his work, getting wickets, bowling dot balls, and not being noticed.
I heard through twitter that people had been calling talkback asking for Mills to be dropped. They called up and talked about the time he got hit for 3 sixes and a 4 in an over by Mark Boucher and Jacques Kallis in 2003/4. They never mention that New Zealand won that game, and that was mostly because in the over before going for all the runs, Mills had bowled an almost perfect over to concede just 3 off the bat when they needed 40 off 3. Nor do they mention that this was right at the start of his career, and that he learned a lot from the experience.
After the first two ODI's in Jamaica, I read a couple of newspaper reports that said that Tim Southee was New Zealand's best bowler. I understand that the two reporters were not actually at the ground, so they may not have had the best perspective, but I fail to see how anyone who watched those games can believe that Southee was a better performer than Mills.
Southee had reasonable figures, but that was in part because New Zealand seemed to have a plan to make sure they kept Gayle at Mills' end. Roughly half the deliveries that Mills has bowled this series have been to Gayle. But he has coped with this task well. Here are the figures for all NZ bowlers to Chris Gayle:
And all New Zealand bowlers against everyone else:
For these tables I've combined the T20's and the ODI's.
I think it is fairly clear who has been the most effective bowler.
Watching the second game live, the battle between Gayle and Mills was fantastic. Mills missed with 3 deliveries and all of them disappeared for 6. The other 30 deliveries that Mills bowled to Gayle in that match conceded just 16 runs.
If New Zealand manage to dismiss Gayle early, Mills will be able to be used at other batsmen. He may well be the trigger that turns the tide in this series. But even if he is, he's unlikely to be celebrated back home.