Duensing's relief stats by season: 2009: 15 G, 31.1 IP, 5.17 ERA, 73% inherited scored (league average ~30%), average Leverage Index .761 (below average) 2010: 40 G, 45 IP, 1.80 ERA, 14% IS, .880 aLI 2011: 4 G, 5 IP, 5.06 ERA, .912 aLI 2012: 44 G, 57 IP, 3.47 ERA, 16% IS, .980 aLI 2013: 39 G, 29.2 IP, 4.55 ERA, 34% IS, 1.363 aLI This is the first season he's been used as a high-leverage-type reliever. Prior to this year, he had a great half season in 2010 and a good half season in 2012. And all through these seasons, his relief K rate has stayed constant in the 5's. He's not a bad reliever, especially given his pre-arb salaries, but it would be a stretch to say "high-quality MLB reliever" given his sample of actual relief pitching. And an even bigger stretch to say he's been maintaining it for five years, when his actual relief pitching sample is more like two seasons. And I would doubt he's ever been considered among the game's elite lefty specialists -- even in his best season of 2010, he wasn't being used as a lefty specialist. That's not to say he can't be a useful piece going forward, but given his salaries are climbing (will be second-time arb eligible this offseason), there's no downside to giving some higher-leverage opportunities to Thielbar instead.