Repentance is also not mentioned here; is repentance, then, not necessary for salvation? It sure is! (See Mt 3:2; Acts 3:19; 2:38; 11:18; 2 Cor 7:10.) So we cannot deny the effect and necessity of sacraments based on this verse. We must bring this verse into harmony with other verses in the Bible to understand all the necessary steps to salvation.
In this passage, Paul is emphasizing justification and salvation through faith as opposed to seeking to establish one's own righteousness without Christ (see Rom 10:3). The argument in verses 9 and 10 is drawn from verse 8, which quotes Deuteronomy 30:14: "But the word is very near you, in your mouth and in your heart, that you may do it" (note the repeated use of the words "mouth" and heart").
The word is in our mouth and in our heart so we may obey it (Deut 30:11-18). Paul cited this passage to show that Christ is the Word become flesh, whom we should confess and believe. This confession and belief is realized in the obedience to Christ—the Word. His argument here was to show that observance apart from Christ cannot attain righteousness. He was not at all saying that confession and belief in Christ removed the need for sacraments. In fact, true confession of and belief in Christ would involve obedience to the Lord's command to receive the sacraments.