When Francisco Alvarez tore his right meniscus back in May, Mets officials bemoaned the fact that, yet again, Alvarez would not enjoy a long, uninterrupted runway to try to make good on his prospect potential. Yet Alvarez returned to the Mets in about half the time those team officials initially estimated, and since his comeback, he’s starting to make strong use of that exact kind of runway. Alvarez hit his fourth homer in nine games Tuesday to lead the Mets to a 3-0 win over the Blue Jays, offering the latest bit of evidence that he can, perhaps once and for all, become an unquestioned middle-of-the-order hitter for these Mets. “We love Alvy,” interim manager Andy Green said. “We’re dying to see him in the lineup consistently. … Alvy has the type of bat that you want to keep out there as often as you can.” Leading off the fifth inning, Alvarez -- serving as the designated hitter, with Luis Torrens catching -- crushed a Kevin Gausman fastball to straightaway center field to break a scoreless tie. Impressive to Green was the fact that, despite Gausman’s ability to bury splitters with two strikes, Alvarez managed to stay on the fastball well enough to hit it a Statcast-projected 415 feet. Two innings later, Torrens added a solo shot of his own off Mason Fluharty (which, fittingly, the Mets’ bullpen catcher caught), making it an awfully productive night for Mets backstops.