Football NEWCASTLE — Pep Guardiola refused to be drawn into a war of words with Jose Mourinho after Manchester City maintained their impressive progress towards the Premier League title. City stretched their commanding advantage at the top to 15 points over Manchester United as Raheem Sterling sealed a 1-0 win at Newcastle to record an 18th consecutive league victory, one short of Bayern Munich’s current best for Europe’s top five leagues of 19 straight wins. United manager Mourinho attempted to provoke Guardiola on Tuesday after pointing to their rivals’ huge spending power by claiming “City buy full-backs for the price of strikers” and insisting that the 300 million pounds (US$402 million) he has spent since taking charge at Old Trafford 18 months ago as “not enough”. Mourinho paid 93 million pounds to sign France midfielder Paul Pogba, while also recruiting £30 million defender Eric Bailly, and midfielder Henrikh Mkhitaryan for 26.3 million pounds. This year, United spent 75 million pounds on striker Romelu Lukaku, as well as 31 million pounds on defender Victor Lindelof and £40 million for midfielder Nemanja Matic. In comparison, City bought three defenders — Kyle Walker from Tottenham for an initial 45 million pounds, Benjamin Mendy…