Phillips looks to continue his red-hot hitting and lead the Reds to a fifth straight win while the Mets may again be without Bay for an extended period starting Saturday night at Citi Field.Phillips is 11 for 22 with three homers and nine RBIs in the past five games, as Cincinnati (36-27) has won four in a row to open up a four-game lead atop the NL Central.The second baseman homered for a third consecutive contest Friday, connecting on a two-run shot to power a 7-3 win over New York (35-30).The Mets' loss may have been compounded when Bay left in the second inning with a possible concussion. The left fielder was hurt when he crashed into the left-field wall trying to catch Jay Bruce's inside-the-park homer.He's expected to go on the disabled list Saturday, the latest setback for a player who has been an injury-plagued disappointment in New York since signing a $66 million, four-year contract before the 2010 season.Bay missed the final two months that season because of a concussion he sustained while slamming into the left-field fence to make a catch at Dodger Stadium."It's a combination of the way he hustles, and bad luck. You feel for him. You know the way he's worked to overcome some of these injuries," third baseman David Wright said. "Obviously, with the head injury, you know you've got to be very careful."Bay is batting .187 with four home runs and six RBIs. He was on the disabled list from April 24 until June 6 with a broken rib and is 2 for 25 since being activated.Scott Hairston will likely step in with Bay out. He hit his sixth homer in his past 14 games Friday after replacing Bay.Giving the ball to Jonathon Niese (4-2, 3.69 ERA) may help the Mets bounce back since he's 2-0 with a 1.75 ERA and 28 strikeouts in 25 2/3 innings over his past four starts. The left-hander has been even better in the last two, allowing only two unearned runs.Niese didn't get much help in Sunday's 5-4 road loss to the New York Yankees, as he left after the seventh with a one-run lead only to watch three relievers allow three runs in the last two innings. He cruised through six before a seventh-inning error by Wright was followed by a two-run homer.Niese is 1-1 with a 5.79 ERA in three starts against Cincinnati, allowing five homers in 18 2/3 innings. Two of those have come off the bat of Phillips, who's 5 for 10 in their matchups.The Reds counter with Homer Bailey (4-4, 4.35), whose last three road starts have resulted in Cincinnati victories. The right-hander is 2-0 with a 2.05 ERA in that stretch.Bailey's last two games ended in Reds home defeats, while he's 0-1 with an 8.38 ERA. He allowed three runs and struck out seven in 6 2/3 innings Sunday against Detroit, leaving with a 6-3 lead before the bullpen allowed four runs in the eighth.Bailey struggled greatly in two starts against the Mets last season, surrendering 13 runs and 21 hits over nine innings.