As Biertempfel noted, Revere would be a good option for the Pirates in the leadoff spot following Josh Harrison's injury. Revere has a ton of speed, stealing 21 bases thus far this season and stealing 49 last season.
Francoeur, on the other hand, could also be a lower-quality replacement for Harrison, as he would be a good bench or platoon player, as the righty has hit pretty well against left-handed pitching over his career, with a .783 OPS.
The Pirates are 52-35 and are in the running for the Wild Card.
On the season, Revere is hitting .294/.335/.377 with a homer, six triples, and 23 runs batted in over 346 plate appearances. Francoeur is hitting .246/.278/.410 with six homers and 26 runs batted in over 194 plate appearances.