(John Kemp is a Reuters market analyst. The views expressed are his own) LONDON, July 19 (Reuters) - Faltering oil prices, triggered by concern over a third wave of the novel coronavirus and increased confidence OPEC+ would boost production, gave portfolio managers a chance to book profits on tactical short positions. Hedge funds and other money managers purchased the equivalent of 24 million barrels in the six most important petroleum futures and options contracts in the week to July 13 (tmsnrt.rs/36MgxAw). The buying partially reversed larger sales of 63 million barrels the week before, position records published by ICE Futures Europe and the U.S. Commodity Futures Trading Commission show. But most of the buying consisted of repurchases of previous short sales (+15 million barrels) rather than the initiation of new long positions (+8 million), implying it was motivated by profit-taking after prices fell. Purchases were spread across NYMEX and ICE WTI (+11 million barrels), Brent (+9 million), U.S. gasoline (+4 million) and U.S. diesel (+3 million), but there were sales of European gas oil (-4 million). On balance, portfolio managers remain bullish, with the net position (901 million barrels) in the 81st percentile and ratio of long to short positions (5.74:1) in the 77th percentile for all weeks since 2013. But there has been little additional strategic buying since the middle of February, when benchmark Brent futures were already trading at $63 per barrel, compared with around $72 in mid-July. As a result, the net position across all six contracts has cycled around 875 million barrels +/- 75 million barrels for the last five months with no discernable trend. Bullishness about output restraint by OPEC+ and U.S. shale producers and the resulting drawdown in inventories has been tempered by worries about resurgent coronavirus cases and their impact on the recovery in oil consumption. This basic balance has remained intact through all the diplomatic drama over how quickly OPEC+ would increase production and disputes about baselines for output allocations. Related columns: - Hedge funds took profits as U.S. oil price hit highest in more than six-years (Reuters, July 12) - U.S. petroleum inventories are becoming tight (Reuters, July 9) - Hedge funds await OPEC+ oil output decision (Reuters, July 5) - Falling U.S. crude stocks draw hedge fund attention (Reuters, June 28) (Editing by Barbara Lewis)